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Transcript
```232/1,232/2,232/3 physics
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
1.
2.
3.
232/1
PHYSICS
Paper 1
JULY/ AUGUST 2016
(THEORY)
Time: 2 Hours
SECTION (25 MARKS)
Answer ALL questions in this section
A micrometer screw gauge has a zero error of -0.02mm. It is used to measure the diameter of a wire. If the actual diameter of
the wire is 0.28mm. Draw the micrometer screw gauge showing the diameter of the wire.
(2 marks)
Figure 1 shows two identical hollow spheres. Sphere A is completely filled with the liquid while B is partially filled with an
identical liquid.
A
B
Figure 1
When the two spheres are rolled on a horizontal surface, it is observed that the sphere B stops earlier than sphere A. Explain
this observation.
(2 marks)
The spiral springs shown in the figure 2 below are identical. Each spring has a constant K = 300N/m.
150N
4.
Figure 2
Determine the extension caused by the 150N weight (Ignore weight of springs and connecting rods)
(3 marks)
A uniform 120m metal rod is pivoted near one of its ends and kept in equilibrium by a spring balance as shown in figure 3.
26cm
12cm
5.
6.
Figure 3
The reading indicated by the spring balance is 2.0N. Work out the mass of the metal rod. (g = 10N/kg)
(3 marks)
A mass of 8kg is whirled round in a vertical circle using a rope of length 80cm if it makes 2.5 cycles in 1 second, calculate
the maximum tension the rope experiences.
(3 marks)
Air is trapped in a thin capillary tube by a thread of mercury 5cm long as shown in figure 4.
Page | 1
232/1,232/2,232/3 physics
Air
16cm
5cm
Mercury
14cm
7.
8.
9.
10.
11.
12.
13.
14.
5cm
Air
Figure 4
Use the information in figure 6 to calculate the value of the value of the atmospheric pressure in mmHg
(3 marks)
A trolley is moving at uniform speed along a track. A piece of plasticine is dropped on the trolley and sticks on it. Explain
why the trolley slows down.
(1 mark)
State a reason why more energy is required to change ice from 0 0C to water at 10C, than to change equal mass of water from
00C to 00C.
(1 mark)
State a reason why an air bubble increases in volume as it rises up the surface in a boiler.
(1 mark)
A car of mass 800kg is initially moving at 25m/s, calculate the force needed to bring the car to rest over a distance of 20m.
(2 marks)
An electric kettle with shiny outer surface is more efficient than one with a dull outer surface, give a reason for this.
(1 mark)
A pipe of radius 3mm is connected to another pipe of radius 9mm. If water flows in the water pipe at a speed of 2ms -1, what is
the speed in the narrower pipe
(2 marks)
A force of 20N is used to stretch a spring through 5cm. Calculate the elastic potential energy stored in the spring.
(2 marks)
SECTION B. (55 MARKS)
Answer ALL questions in this section
(a) Distinguish between boiling and evaporation.
(2 marks)
(b) A solid of mass 1kg was heated uniformly by a 100W heating element until it melts. The graph in
figure 5 shows the variation of temperature with time.
Z
Temp (0C)
80
Y
X
20 W
Time (s)
200
100
300 400 500
Figure 5
(i) Explain what is happening in the regions
WX:
XY:
(ii) Calculate the specific heat capacity of the solid.
(3 marks)
(iii) Calculate the specific latent heat of fusion of the solid
(2 marks)
(c) A substance of mass 2kg and specific heat capacity 400Jkg-1k-1 initially at 800C is immersed in water at 190C. If the final
temperature of the mixture is 200C. Calculate the mass of water. (Specific heat capacity of water = 4200Jkg -1k-1)
(3 marks)
15. (a) State the physical quantity represented by the gradient of a displacement – time graph
(1 mark)
(b) Figure 6 shows the displacement – time graph of the motion of a particle
C
Displacement (m)
A
B
O
D
Time (s)
Figure 6
State the nature of the motion of the particle between?
(3 marks)
(i) AB
(ii) BC
(iii CD
(c) A car decelerates uniformly from a velocity of 20m/s to rest in 4 seconds. It takes 4 seconds to reverse with uniform
Page | 2
232/1,232/2,232/3 physics
acceleration to its original starting point.
(i) Sketch a velocity time graph for the motion of the car.
(3 marks)
(ii) Use your sketch in c (i) to determine the total displacement of the car.
(3 marks)
(d) A ball slides off a horizontal table 4m high with a velocity of 12m/s, find;
(i) the time it takes to hit the floor. (g = 10ms-2)
(2 marks)
(ii) the range
(2 marks)
16. (a) State two factors that reduce the stability of a vehicle while going round a banked bend.
(2 marks)
(b) Three insoluble powders A, B and C of densities d A, dB and dC, such that dA> dB > dC, are mixed and put into a container.
The container is then whirled in a horizontal circle as shown in figure 7.
Centre of rotation
Container
Figure 7
(i) Label on figure 7, the positions of the powders after some time.
(1 mark)
(2 marks)
(c) Figure 8 shows two masses 0.1kg and 2kg connected by a string through a hole on a smooth horizontal surface.
3cm
0.1kg
Smooth horizontal surface
2kg
Figure 8
The 0.1kg rotates in a horizontal circle of radius 3cm. Calculate the angular velocity of the 0.1kg mass,
system is in equilibrium.
(d) A bicycle wheel makes 300 revolutions per minute. Calculate the angular velocity of the wheel.
17. (a) State two conditions for a body to float on a fluid.
(b) Figure 9 shows a block with a graduated side and dimensions 4cm by 16cm, just about to be lowered
into a liquid in an overflow can.
when
the
(3 marks)
(3 marks)
(2 marks)
Block
Overflow
Liquid
Beaker
Liquid
Balance
Figure 9
During an experiment with this set-up, the following was recorded:
- The block floated with of it submerged.
- Initial reading of balance = 0g
- Final reading of balance = 154g
Use the information to determine the density of
(i) the block
(ii) the liquid
(c) Figure 10 shows a buoy of capacity 40 litres and mass 10kg. It is held in position in sea water of
density 1.04g/cm3 by a light cable fixed to the bottom so that ¾ of its volume is below the water surface.
(3 marks)
(3 marks)
Page | 3
232/1,232/2,232/3 physics
Buoy
Water
Cable
Sea bed
Figure.10
Determine the tension in the cable.
18. Figure 11 shows a load of 50N being raised by pulling it along an inclined plane of length 2.0m.
2.0m
Figure 11
Determine
i. The work done by the 22N force
ii. The work done against the load
iii. The efficiency of the system
(3 marks)
h = 0.5m
(2 marks)
(2 marks)
(3 marks)
Page | 4
232/1,232/2,232/3 physics
1.
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
232/2
PHYSICS
Paper 2
(THEORY)
JULY / AUGUST 2016
Time: 2 Hours
Figure 1 below shows a parabolic surface with focal point F. A small source of light is placed at F.
F
2.
3.
Fig. 1
Complete the ray diagram to show the incident rays are reflected by the surface.
Figure 2 below shows a metre rule in equilibrium balanced by the magnet and weight. The iron core fixed to the bench.
Fig. 2
State and explain the effect on the metre rule when the switch S is closed.
(2 marks)
The figure 3 below shows a positively charged metal plate with an earthing connection. Using an arrow, show the direction of
charges through the earth connection and explain the final charge of the plate.
(2 marks)
+++++++++++++++++
+++++++++++++++++
4.
5.
6.
Metal plate
Fig. 3
A current of 0.7A flows through a wire when a potential difference of 0.35V is applied at the ends of the wire. If the wire is
0.5m long and has a cross-sectional area of 8.0 x 103mm2, determine its resistivity.
(3 marks)
The control grid in a cathode ray oscilloscope (CRO) is used to control the brightness of the beam on the screen. Explain how
the brightness of the beam can be increased
(2 marks)
The following figure 4 shows the path of a ray of light through a transparent material placed in air.
Air
Ray of light
7.
8.
420
Transparent
Material
Fig. 4
Determine the refractive index of the transparent material
Give a reason why x-rays but not radio waves are used to detect fractured bones.
(1mark)
One of the factors that affect efficiency of a transformer is hysteresis losses. What is hyteresis losses
(2 marks)
Page | 5
232/1,232/2,232/3 physics
9.
A vibrator is sending out 8 ripples per second across a ripple water tank. The ripples are observed to be 4cm apart. Calculate
the velocity of the ripples
(2 marks)
10. A form two student from Kimomo Secondary School found his dry cells leaking on removing from his torch. What would be
the possible cause of the leakage
(2 marks)
11. A sample of a radioactive substance initially has 8.0 x 10 25 particles. The half life of the sample is 98 seconds. Determine the
number of particles that will have decayed after 294 seconds.
(3 marks)
12. Below is part of a circuit that was setup by form four students of Okok Seconday School during a physics practical lesson to
demonstrate full wave rectification using two diodes. Complete the circuit by correctly placing the load R and two diodes.

Fig. 5
13. State two factors that affects the speed of sound in gases.
(2 marks)
SECTION B (55 MARKS)
Answer ALL the questions in the spaces provided
14. Some students wish to determine the focal length of a convex lens of thickness 0.6cm using an optical pin and a plane mirror.
Figure 6 shows the experimental set up when there is no parallax between the pin and the image.
Pin
Image of pin
20cm
Plane mirror
Fig. 6
Determine the focal length of the lens
(b) An optician in Eldoret Hospital examined an eye of a patient and made the following observations:
Eye too short and the focal length of the eye lens short
(i) State the eye defect the patient could be having.
(ii) Use a diagram to describe how the defect could be corrected.
(c) The graph below shows the variation of 1/v and 1/u in an experiment to determine the focal length of a lens.
(2 marks)
(1 mark)
(2 marks)
0.3
1
𝑣
m-1 0.2
0.1
Fig. 7
0.1
0.3
0.3
1
𝑢
m-1
(i) Use the graph to determine the focal length
(3 marks)
(ii) What is the power of the lens used?
(2 marks)
(d) A converging lens forms an image which is three times the object. Determine the focal length of the lens if the distance
between the object and the screen is 80cm.
(3 marks)
15. (a) An uncharged metal rod brought close but not touching the cap of a charged electroscope causes a decrease in the
divergence of the leaf. Explain the observation.
(1mark)
(b) In experiment to investigate factors affecting capacitance of a capacitor, a student increased the area of the plates and
decreased the separation of the plates. Explain the effect on the capacitance when
(i) the area of plates increased
(1 mark)
(ii) the distance of the separation of the plates decreased
(1 mark)
Page | 6
232/1,232/2,232/3 physics
(c) Figure 8 illustrates a method of charging a metal sphere.
(i)
Fig. 8
+
+
+
+
(ii)
+
+
+
+
(iii)
(i) Name the method of charging shown in fig 8.
(ii) Indicate the final charge on the sphere in fig 8.
(d) Figure 9 shows an arrangement of capacitors connected to a 10V d.c supply.
10V
(1 mark)
3F
2F
3F
1F
Fig.9
Determine
(i) the combined capacitance
(ii) the total charge in the circuit
(iii) the total energy stored in the circuit.
16. Figure 10 shows photocell used in a set-up for a burglar alarm.
(2 marks)
(1 mark)
(2 marks)
UV Light
A
Relay
To burglar alarm
Fig. 10
(i) Give a reason why the photocell is usually evacuated.
(ii) State the function of the resistor R in this circuit
(iii) Explain why a particular radiation such as ultra-violet light is used to strike a given cathode surface.
(iv) Explain how the set-up in the figure can be used as a burglar alarm.
(b) Light of frequency 5.50 x 10 14 Hz is incident on a surface whose work function is 2.5ev.
(i) Determine the energy of photons of light in eV. (Take h = 6.63 x 10 -34 Js) and 1eV
(ii) Will photoelectric emission occur? Explain
17. (a) Define electric resistance.
(b) Figure 11 shows three resistors as shown.
(1 mark)
(1 mark)
(2 marks)
(3 marks)
(3 marks)
(2 marks)
(1mark)
V
6
8
Fig. 11
3
Page | 7
232/1,232/2,232/3 physics
If the voltmeter reads 4V, find the
(i) Effective resistance
(2 marks)
(ii) Current through the 3 resistor
(2 marks)
(iii) Potential difference across the 8 resistor.
(2 marks)
(c) (i) What is meant by the term ―lost volts‖?
(1 mark)
(ii) A cell supplies a current of 0.5A when connected to a 2 resistor and 0.25A when connected to a 5 resistor.
Find the e.m.f and the internal resistance of the cell.
(4 marks)
18. Figure 12 shows a diffusion cloud chamber for detecting radioactivity.
6Perspex lid
Felt ring soaked in alcohol
Source
Dry ice (Solid CO2)
Sponge
Fig. 12
(a) State the function of the following.
(I) Alcohol
(1 mark)
(II) Solid CO2
(1 mark)
(b) When radiation from the source enters the chamber, some white traces are observed.
(I) Explain how the traces are formed.
(1 mark)
(II) State how the radiation is identified
(1 mark)
(c) A leaf electroscope can be used as a detector of radiation. State two advantages of the diffusion cloud chamber over the leaf
electroscope.
Page | 8
232/1,232/2,232/3 physics
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
PHYSICS PAPER 232/3
PRACTICAL
CONFIDENTIAL
Q1. Each candidate should have the following;
 A rectangular glass of dimensions about
l – 10cm
w – 6.3cm
t – 1.8cm
 Four optical pins
 30cm transparent ruler
 Protractor
 A plain white paper fixed on the soft board
NB: The teacher to fix the sheet of paper for the candidate.
The teacher ensures the candidates removes the sheet of paper and attach it to the question paper for marking.
Q2. Each candidate should have the following
 Voltmeter 0 – 5V
 Ammeter 0 – 1A
 Micrometer screw gauge to be shared.
 Switch
 2 new dry cells – Size D
 8 connecting wires
 A wire AB – mounted on a mm scale SWG 28
NB: Teacher to mount the wire and label it as AB.
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
232/3
PHYSICS PRACTICAL
Paper 3
JULY/ AUGUST 2016
TIME: 2 ½ HOURS
Q1. You are provided with the following:
 A plain white paper fixed on the softboard
 Four optical pins
 30cm transparent ruler
 Protractor
 Rectangular glass block
Proceed as follows:
(a) On the white sheet of paper fixed on the softboard, draw a line XY, 25cm long at the middle of the paper. Mark its point at Q.
 At Q draw a normal, QN.
 Draw a line PQ such that the angle, i, between PQ and QN is 15 0.
(b) Place the glass block, largest face down, on the paper such that the mid-point of the edge AB of the block coincides with the
mid-point Q of the line XY as shown in figure 1. Draw the outline, ABCD, of the glass block.
 Fix two pins O1 and Q2 on the line PQ in such a way that they are vertical and about 5cm from each other.
 Looking through the glass block through face AB, fix two pins S 1 and S2, so that they are exactly in line with O1 and O2
AS shown in figure 1.
 Mark the positions of S1 and S2.
 Remove the block, joint points S1 and S2 and produce the line to meet face AB of the block at R.
 Join Q to R.
 Measure the length, QR, let its length be L = ____________ cm
(c) Repeat part (b) for other values of angle i = 25 0, 350, 450 and 550 and complete table 1.
Page | 9
232/1,232/2,232/3 physics
N
O1
O2
X
D
Q
C
Y
L
A
M
B
S1
S2
S
Figure 1
NB: Attach the sheet of paper to the question paper for marking.
Table 1
i ( 0)
L(cm )
L2 (cm2) 1 (cm-2)
Sin i
Sin2i
15
25
35
45
55
1
(d) On the grid provided, plot a graph of (vertical axis) against sin2i
(e) Determine the slope of the graph
(f) Given that,
1
1
1
=
Sin2i
Use the graph for find;
(i) b
(ii) n
Q2. You are provided with the following
 A wire AB mounted on a mm scale.
 A voltmeter screw gauge
 A switch
 2 cells
 A cell holder
 8 connecting wires
(a) (i) Arrange the apparatus and then connect the circuit as shown in the diagram.
(1 mark)
(5 marks)
(2 marks)
(3 marks)
(3 marks)
A
B
A
J
V
Nichrome wire
(ii) Close the switch and record the value of current, I, flowing.
I = ________________________ A
(1 mark)
Page | 10
232/1,232/2,232/3 physics
(b) Place the sliding contact J at a distance of 10cm from A. Read the p.d across the wire. Increase the length AJ to the values
shown each time obtain the p.d across the wire.
(c) Enter these values in the table below.
(5 marks)
Length L (cm)
10
20
30
40
50
60
P.d across AJ (N)
(d)
(e)
(f)
(g)
(h)
Pot a graph of p.d (v) (y-axis) against length L
Determine the slope S, of your graph.
Determine the diameter of the wire AB at two different points hence calculate the average.
Determine the cross-section area, A, of the wire in cm2
Given that V = , determine the value of k.
(5 marks)
(3 marks)
(2 marks)
(2 marks)
(2 marks)
Page | 11
232/1,232/2,232/3 physics
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
PHYSICS PAPER 232/1
PAPER 1
MARKING SCHEME
1.
35

0
30
25
2.
3.
0.28+0.02
= 0.30mm
In A the C.O.G stays at the same place throughout while in B, C.O.G changes hence resisting motion. 
= 0.5m 
For 3 parallel e = = 0.1667
4.
For 2 springs parallel in e = = 0.25m
Total extension 0.1667 + 0.25 = 0.4167m 
Clockwise moment = Anticlockwise moment
0.48 x = 0.34 x 2.0
w=
m=
1 1
1
= 141.67g
5. w = 2
3.142 x 2 x 2.5 = 15.71 rad/sec
T = mw2r
= 8 x (15.71)2 x 0.8
= 1579.5N
6. P1 = (PA + 5) cmHg
P2 = (PA – 5) cmHg
V1 = 14cm
V2 = 16cm
P1V1 = P2V2 
(PA + 5) (14) = (PA-5)16
 14PA + 70 = 16PA – 80
2PA = 150
PA = 75cmHg
7. Plasticine increases the mass of the trolley, since momentum is conserved, increasing mass reduces velocity. 
1
mx
8. Extra energy has to be used for change of state. 
9. As it rises the pressure decreases hence volume increases. 
10. V2 = u2 + 2as
O2 = 252 + 2 x a x 20
40a = -252
a = -15.625 m/s2
F = ma
= 800 x -15.625 
= -12500N
Breaking force 12500N 
11. Shinny surface reduce heat loss through radiation since they are emitters of heat. 
12. Smaller area A1 =
= 3.14 x 3 x 3
= 28.26mm2
Wider area A2 =
= 3.14 x 9 x 9
= 254.34m2
A1V1 = A2V2
28.26 x V1 = 254.34 x 2 
V1 =
Page | 12
232/1,232/2,232/3 physics
= 18m/s 
1
13. Elastic P.E =
1
= ( )x(
= 0.5J 
) 
14. (a)
Boiling
Evaporation
 Takes place at a fixed temperature
 Take place at all temperatures
 Takes place throughout the liquid, with  Takes place on the surface of the liquid
bubbles of steam forming all over
 No bubbles formed
(b) (i) WX – Solid absorbing heat hence temperature rise 
XY – The solid is melting at 800C. 
(ii) pt = mc
100 x 100 = 1 x c x (80 – 20) 
1
1
c=

= 166.67Jkg-1k-1
(iii) pt = mLf
(100 x 200) = 1 x Lf 
Lf = 100 x 200
= 20,000 Jkg-1 
(c) Heat lost by solid = Heat gained by water
mscs = mwew
2 x 400 x (80 – 20) = m x 4200 x (20-19) 
m=
 = 11.43kg 
1
15. (a) It gives velocity of a body 
(b) (i) Particle is at rest (stationary) 
(ii) Velocity increasing non-uniformly 
(iii) Velocity decreasing uniformly 
(c) (i)
V (m/s)
20
 Axes well labelled
 Scale (Uniform)
 Graph
10
0
-10
-20
8
4
Time (s)
(ii) Displacement = Area under graph  realizing
1
=
(
= 40 – 40
=0m
)- (
1
)
(d)
4m
(i) 4 =
=
1

R
1
t2 = 
t = 0.89 sec
(ii) R = UT
= 0.89 x 12 
= 10.68m 
16. (a) – High speed 
Page | 13
232/1,232/2,232/3 physics
(b) (i)
C
B
A
 Order
(ii) Denser powders require more centripetal force hence moves away from the centre of rotation,
while lighter ones moves towards the centre of rotation. 
(c) T = 2 x 10= 20N 
But T = mw2r
20 = 0.1w2 x 0.03
= 0.003w2
w2 =
= 6.6667
(d) w = 2 
= 2 x 3.142 x = 31.42 rad/sec 
17. (a) – Must be less dense than the fluid 
- Must displace its own weight
(b) (i) Volume of block = 16 x 4 x 4
= 256 cm3
Mass = 154g
Density of block =

=
1
= 0.60g/cm3
(ii) Volume of liquid displaced =
 = 192cm3
Density of liquid =
1
=
 = 0.80g/cm3 
1
(c) Upthrust = wt of water displaced
=
= 30, 00cm3
Mass displaced = 30,000 x 1.04 = 31200g
Wt. displaced = 312N 
T = u – wt
312 – 100  = 212N 
18. (i) Work done = Force x distance
= 22 x 2  = 44Nm (J) 
(ii) Work done = mgh
= 50 x 0.5
= 25J
1
(iii)
=
 = 56.82% 
Page | 14
232/1,232/2,232/3 physics
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
PHYSICS PAPER 232/2
PAPER 2
MARKING SCHEME
1.
 Parallel reflected beam
F
2.
3.
The metre rule will tip in anticlockwise direction. This is because when the switch S is closed the iron core becomes
magnetized with the top of the core becoming a south pole hence attracts the north pole of the magnet. Accept end A move
down while end B up.
a
+++++++++++++++++
+++++++++++++++++
Metal plate
Insulator
Figure 1
The electrons flow from the earth and neutralizes all  the positive charges in the plate leaving the plate neutrally charged.
1
4.
=
5.
= 8.0 x 10 m  Award with  units
– By making the grid more positive with respect to the cathode 
- This males many electrons reach the screen hence the spot becomes brighter. 
6.
an g


-3
=
an g =
1
= 1.494
X – rays have more penetration power. Accept: X-rays have high frequency/energy
Hysteresis losses are loss of energy in form of heat during magnetization and demagnetization of the transformer core. 
f = 8HZ
 = 0.04M
V = F 
= 0.04 x 8= 0.32 m/s 
10. The depolarizer manganese (IV) oxide  has oxidized hydrogen gas produced during polarization to water.
11. No. of half-lives = = 3 
7.
8.
9.
8.0 x 1025  4.0 x 1025  1.0 x 1025
No. of particles remaining = 8.0 x 10 25 – 1.0 x 1025
= 7.0 x 1025 
1
OR N = No ( )
1
= 8.0 x 1025 x ( )
1
= 8.0 x 1025 x = 1 x 1025 
Number remaining = 8.0 x 1025 – 1.0 x 1025
= 7.0 x 1025 
12.

R TO C.R.O
13. - Density of the gas  1
- Humidity 
- Pressure 
Page | 15
232/1,232/2,232/3 physics
- Temperature 
- wind 
14. (a)
f = 20 – 0.3 = 19.7cm
(b) (i) Long sightedness (hypermetropia)
(ii)
Rays from a distance
object
1
(c)(i) at intercept,
1
1
f = 3.33
1
1
at intercept,
f = 3.33
fav =
(ii) P =
1
1
= 3.33m
1
=
= 0.30D
1
(d) m = 
f=
u + v = 80cm
= 15cm
u = 20cm
15. (a) A metal rod is a good conductor of charge hence the electroscope 
(b) (i) Increase 
(ii) Increases 
(c) (i) Induction 
(ii) Electrons from the earth to the sphere  to neutralize the repelled positive charges 
(iii) Negative charges 
(d) (i) Series =
= = 1.5F
in parallel with 2F
CT = 1.5 + 2 = 3.5F
In series with 1F
1

CT =
=

1

= 0.78F
= 7.8 x 10-7F 
(ii) 7.8 x 10-7 x 10 
= 7.8 x 10-6 C
(iii) E = ½CV2 
= ½ x 7.8 x 10-6 x 10 
= 3.9 x 10-5J 
16. (a) (i) To ensure that all the electrons emitted by the cathode reach the anode to maximize the photocurrent.
(ii) To limit control or lower the current in the circuit.
(iii) The energy of the incident light must be greater than work function of the cathode surface if photoelectron emission
has to occur.
(iv) The current flowing in the circuit ensures that the relay switch is attracted to the electromagnet.
When UV light is cut-off, the photocurrent ceases and the relay switch completes the burglar alarm circuit and the
alarm sounds.
(b) (i) e = hf
= 6.63 x 10-34 x 5.5 x 1.4 = 3.6465 x 10-19J
1
In eV =
= 2.2791eV
1
1
(ii) No, the energy of the incident photon is less than the work function of the surface.
17. (a) Opposition offered by a conductor to the flow of electric current.
1
1
1
1
(b) (i)
R = 2
Rtotal = 2 + 8 = 10
(ii) I =
(iii) I =
1
V = IR = 0.4 x 8 = 3.2V
(c) (i) The voltage lost due to internal resistance.
Page | 16
232/1,232/2,232/3 physics
(ii) E = IR + 1r
E = 0.5 x 2 + 0.5r……………(i)
E = 0.25 x 5 + 0.25r …………(ii)
E = 1 + 0.5r
E = 1.25 + 0.25r
18. (a) (I) To produce alcohol vapour  which diffuse down to be cooled. 
(II) To cool the vapour below condensation temperature. 
(b) (I) Radiation from the source ionizes air along its path, alcohol condenses around these ions forming
droplets on traces. 
(II) Nature of traces identifies radiation. 
(c) - Can detect alpha and beta particles, leaf electroscope cannot. 
- It is more sensitive. 
MAKUENI COUNTY CLUSTER PREPARATORY EXAMINATION 2016
PHYSICS PAPER 232/3
PAPER 3
MARKING SCHEME
X
Y
(c)
i (0)
l(cm)
l2(cm2)
15
25
35
45
55
6.6
6.8
7.0
7.4
7.8
43.56
46.24
49.00
54.76
60.84
(
0.023
0.022
0.020
0.018
0.016
)
Sin i
Sin2i
0.2588
0.4226
0.5736
0.7071
0.8192
0.067
0.179
0.329
0.50
0.671
Max. – 6mks
Page | 17
232/1,232/2,232/3 physics
S–1
A–1
P–2
L-1
Max5
(d)
(e) Slope =
Linear and appropriate
Well labelled with units
All points

=

(
) 1
(

) 1
=
-1
= -0.01154cm  With units
(f) (i)
1
1
= - x is intercept  Realizing
= 2.4 x 10-2 cm-2  - value extracted
1
b2 =
1
b2 = 41.66
b = 6.455cm 
(ii)
1
1
= gradient  Realizing = 0.01154cm3  - for equating
=
1
n2 = 2.080
n = 1.442
(a) (ii) I = 0.16 A  0.05
(c)
Length
10
20
Pd (V)
0.25
0.50
All values 5 mks correct
At least 5 correct 4 mks
(e) S =
1
1
= 0.025
30
0.75
40
0.95
50
1.25
60
1.50
70
1.75
Intervals 
 With units
 No units 1 mk
(f) d =
(g) A = 3.142 x
 = 0.555mm 
1
11
1
1

2
= 9.899 x 10-4cm 
(h) Slope = m  Realising
0.025 =
k = 0.025 x 0.000989 =

Page | 18
232/1,232/2,232/3 physics
MOKASA JOINT EXAMINATION
232/1
Physics
Paper 1
March / April 2016
Section A (25Marks)
1. The diagram below shows a micrometer screw gauge. What is the reading in SI units?
2.
3.
4.
5.
6.
7.
8.
(2 marks)
Apart from friction, name another factor that reduces efficiency in machines.
(1 mark)
Diffusion in gases is faster than in liquids; state two reasons why this is so.
(2 marks)
A tube of radius 9 mm has a constriction of diameter 10mm. Water flows in the tube at 3ms -1. Determine the velocity of water
in the constriction.
(3 marks)
(a) A student obtained ice at 0oCfrom a refrigerator and placed it in a beaker on a bench. After 4 minutes, the temperature
rose to
4oC. State the changes that would be observed in the water in terms of;
(i) density
(1 mark)
(ii) mass
(1 mark)
(ii) volume
(1 mark)
The diagram below shows a uniform 5m long metal rod of mass 800g. It is suspended by a string tied at a point 3.5m from
one end. Determine the load which should be hung at point X to keep the plank horizontal.
(3 marks)
Explain why ice skaters use sharp-edged shoes to slide on ice
The diagram below shows a braking system.
(2 marks)
Why is the master piston, made smaller than the slave piston?
(1 mark)
9. A faulty thermometer reads 2oC when dipped in ice at 0oC and 95oC when dipped in steam at 100oC. What would this
thermometer read if placed in water at room temperature at 18 oC?
(3 marks)
10. The figure below shows a machine being used to raise a load. Use the information given in the figure to answer questions
below.
Determine the efficiency of the machine.
11. Using Kinetic theory of matter, explain why solids expand when heated
(3 marks)
(2 marks)
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232/1,232/2,232/3 physics
Section B (55 Marks)
12. A bullet of mass 24g travelling in a horizontal path with a velocity of 450ms -1 strikes a wooden block of wood of mass 976g
resting on a rough horizontal surface. After impact, the bullet and the block move together for a distance of 7.5m before
coming rest.
(a) Name the type of collision which takes place above
(1 mark)
(b) What‘s the velocity of the two bodies when they start sliding
(2 marks)
(c) Calculate the force which brings the two bodies to rest
(3 marks)
(d) Determine the coefficient of friction between the block and the surface during this motion.
(2 marks)
13 (a) Give reason why a body moving in a circular path with constant speed is said to be accelerating.
(1mark)
(b) A stone of mass 40g is tied to the end of a string 50cm long such that it is 20m above the ground at its lowest level as
shown
in the diagram below. It is whirled in a vertical circle at 2rev/s.
(i) If the string breaks at its lowest levelas shown, what is the velocity with which it travels?
Calculate the maximum tension in the string.
(ii) Calculate the maximum tension in the string.
(d) Determine the maximum horizontal distance it travels from the breaking point
14 (a) Give reason why ink is most likely to ooze out of a pen when one is up in an airplane.
(b) The figure below is a simple hydraulic machine used to raise heavy loads.
Calculate;
(i) The pressure exerted on the oil by the force applied at A
(ii) The load raised at B
(iii) Give two properties which make the oil suitable for use in this machine
(2 mark)
(3marks)
(2 marks)
(2 marks)
(1mark)
(2marks)
(2marks)
(2marks)
(c) The height of a mountain is 1360m. The barometer reading at the base of the mountain is 74cmHg. Given that the densities of
mercury and air are 13,600Kgm-3 and 1.25Kgm-3 respectively, determine the barometer reading at the top of the mountain.
(3
marks)
15 (a) State Hooke‘s Law
(1mark)
Page | 20
232/1,232/2,232/3 physics
(b) The diagram below shows a graph of force against extension for a certain spring.
Force
(N)
Extension (cm)
(i)
(ii)
16. (a)
(b)
What is the spring constant of the spring?
(2 marks)
What force would cause two such springs placed side by side to stretch by10cm
(3 marks)
What is meant by specific latent heat of fusion of a substance?
(1mark)
In an experiment to determine the specific latent heat of vaporization of water, steam at 100ºC was passed into water
contained in a well-lagged copper calorimeter. The following measurements were made:
 Mass of calorimeter = 60g
 mass of water + calorimeter = 145g
 Final mass of calorimeter + water + condensed steam = 156g
 Final temperature of the mixture = 48oC
[Specific heat capacity of water = 4200JKgˉ¹kˉ¹ and specific heat capacity of copper = 390JKgˉ¹kˉ¹]
Determine the;
(i) mass of condensed steam.
(1mark)
(ii) The heat gained by the water and calorimeter if the initial temperature of the calorimeter and water is 20ºC. (3marks)
(iii) Given that Lvis the specific latent heat of vaporization of steam, write an expression for the heat given out by steam.
(1mark)
(iv) Determine the value of Lv above
(2marks)
(v) State the assumption made in the above experiment
(1 mark)
17. A cork of volume 100cm3 is floating on water. If the density of the cork is 0.25 gcm-3 and that of water is 1 gcm-1;
(a) Calculate the mass of the cork
(2 marks)
(b) Hence, find the upthrust force on the cork
(2 marks)
(c) What minimum force is required to immerse the cork completely
(2 marks)
(d) What is the effect on the upthrust force in a liquid when the temperature of the liquid is reduced?
(1mark)
18. (a) State Pressure Law
(1mark)
(b) The following diagram shows a set up of apparatus used to verify Charles Law.
X
(i) Give the name of part labelled X
(1 mark)
Page | 21
232/1,232/2,232/3 physics
(ii) What is the function of the part named in (i) above?
(1 mark)
(iii) Briefly explain how the set up above is used to verify Charles Law
(3 marks)
(c) A certain mass of hydrogen gas occupies a volume of 1.6m3 at a pressure of 1.5x105Pa and a temperature of 120c. Determine
the volume when the temperature is 00c at a pressure of 1.0x103Pa.
(2 marks)
Page | 22
232/1,232/2,232/3 physics
1.
MOKASA JOINT EXAMINATIONS
Kenya Certificate of Secondary Education (KCSE
232/2
PHYSICS
Paper 2
(Theory)
March/April 2016
2 hours
Section A (25 marks)
Answer ALL the questions in the spaces provided.
Figure 1 show a ray of light incident on a plane mirror.
Plane mirror
Figure1
2.
3.
4.
5.
6.
(a) On the diagram, indicate the direction of the reflected ray.
(1mark)
(b) Give reason for the path shown above.
(1mark)
State what happens to the image when one moves closer to the object when using a pinhole camera.
(1mark)
An object of height 2 cm is placed 25 cm in front of a concave mirror. A real image is formed 75 cm from the mirror.
Calculate the height of the image.
(2marks)
State the law of magnetism.
(1mark)
State and explain the functions of the keeper when storing magnets.
(2marks)
Figure 2 shows a steel bar to be magnetized.
Steel bar
Figure 2
7.
P
Q
Complete the circuit such that both poles P and Q acquire opposite polarity (North- south respectively).
Figure 3 shows a set up of a simple cell.
(1mark)
Bulb
Figure 3
Zinc
A
B
8.
(a) Name the electrode A and electrolyte B.
(b) State two reasons why the bulb goes off a short time.
(c) Give one method of minimizing the defect that occurs in plate A.
The chart below shows part of the electromagnetic spectrum.
Visible light
A
B
(a) Identify the radiation marked A and C.
(2marks)
(2marks)
(1mark)
UV light
C
(1mark)
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232/1,232/2,232/3 physics
(b) Give one application of the radiation marked B.
(1mark)
The range of audible frequencies varies from 20 Hz to 20 kHz. If the speed of sound is 340 m/s, what is the corresponding
range of wavelength?
(3marks)
10. Distinguish between transverse waves and longitudinal waves.
(1mark)
11. Figure 4 shows a wave form
9.
Distance (m)
Figure 4
3.0
0
0. 4
0. 2
0.8
0.6
Time (ms)
-3.0
Determine the wavelength given that the speed of the wave is 400 m/s.
(2marks)
12. An electric kettle is rated at 1.8 kW, 240 V. Explain the choice of the safest fuse for the kettle. (the available fuses are 5 A, 10
A, and 20 A)
(3marks)
Section B (55 marks)
Answer ALL the questions in the spaces provided.
13. (a) A bar magnet is pushed into a coil as shown in Figure 5 below.
Figure 5
N
S
Motion
Galvanometer
(i)
(ii)
(b)
(c)
(i)
(ii)
14.
Explain what happens to the pointer of the galvanometer when the magnet is:
Moved into the coil rapidly?
(1mark)
Remains stationary inside the coil?
(1mark)
State two ways of increasing the magnitude of induced current in a generator.
(2marks)
A transformer has 200 turns in the primary coil and 1000 turns in the secondary coil. The primary coil is connected to an a.c
source producing 100 V and rated 500 W. The current delivered by the secondary circuit was found to be 0.95 A.
Determine the efficiency of this transformer.
(3marks)
Explain why the efficiency is less than 100%.
(2marks)
(a) A coin is placed at the bottom of a tall jar. The jar is filled with paraffin to a depth of 32.4 cm and the coin is apparently
seen displaced 9.9 cm from the bottom. Determine the refractive index of air with respect to paraffin.
(3marks)
(b) Define the term critical angle.
(1mark)
(c) Figure 6 shows a ray of light passing through a glass prism.
θ
Figure 6
0
60
0
60
If the speed of light in prism is 2.0 x 10 8m/s
Page | 24
232/1,232/2,232/3 physics
8
(i) Determine the refractive index of the prism material given that the speed of light in air is 3.0 x 10 m/s.
(ii) Determine the value of the critical angle c and show it on Figure 6.
15. (a) Differentiate between an Ohmic and non-ohmic conductor giving one example in each case.
(b) Figure 7 shows a circuit with resistors and voltmeter connected to a battery.
Figure 7
S
6.0V
V
(2marks)
(2marks)
(2marks)
3Ω
5Ω
2Ω
(i) If each cell has an internal resistance of 0.7Ω, determine the total resistance in the circuit.
(3marks)
(ii) What amount of current flows through the 3Ω resistor when the switch is closed?
(3marks)
(iii) What is the reading of the voltmeter when the switch S is
(I) Open
(1mark)
(II) Closed
(1mark)
(iv) Account for the difference between the answers in (I) and (II) above.
(1mark)
16. Figure 8 shows an electromagnetic relay being used to switch an electric motor on and off. The electromagnet consists of a
coil of wire wrapped around a core. The motor in figure is switched off.
Springy metal strips
Figure 8
A
Motor
Contacts
B
Pivot
Soft iron armature
Insulator
Core
S
(a)
(b)
(c)
(d)
(i)
(ii)
(e)
(f)
Suggest suitable material for the core.
What happens to the core when switch S is closed?
Why do the contacts A and B close when the switch S is closed.
When the switch S is opened, what will happen to;
The core
Soft iron armature.
Give one other application of an electromagnet.
State two ways in which an electromagnet could be made more powerful.
(1mark)
(2marks)
(2marks)
(1mark)
(1mark)
(1mark)
(2marks)
Page | 25
232/1,232/2,232/3 physics
17. (a) Give a reason why a candle flame is blown when a highly charged conductor is brought close to it as shown in Figure 9.
(2marks)
Figure 9
++++++
++++++
Highly charged conductor
Flame
Candle
(b) Figure10 shows 1μF, 2μF, 4μF and 5μF capacitors connected to a battery.
1μF
Figure 10
5μF
4μF
2μF
8.0 V
Determine:
(i) The total capacitance.
(2marks)
(ii) The total charge.
(2marks)
(iii) Voltage across the 4μF capacitor.
(2marks)
18. (a) In an experiment to observe interference of light a double slit experiment was placed close to the monochromatic source
as shown in Figure 11.
Figure 11
S1
Monochromatic
source
S2
(i) State the function of the double slit.
(ii) Describe what is observed on the screen.
Screen
(1mark)
(2marks)
(b) Figure 12 shows an object O placed in front of a diverging lens whose principal focus is F.
Figure 12
O
F
Page | 26
232/1,232/2,232/3 physics
On the diagram, draw rays diagram to locate the image formed.
(c) Figure 13 shows a defective eye focusing a distant object.
(3marks)
Figure 13
Rays from a distant object
(i) Name the defect.
(1mark)
On the same diagram, sketch the appropriate lens to correct the defect and sketch the rays to show the effect of the lens.
(2marks)
Page | 27
232/1,232/2,232/3 physics
MOKASA JOINT EXAMINATION
232/3
PHYSICS PRACTICAL
2 ½ Hours
REQUIREMENTS
Each candidate should be provided with:
1. - A rectangular glass block
- 4 optical pins
- A soft board
- A plain paper
2. (I) - A voltmeter (0 – 3V)
- An ammeter (0 – 1A)
- A dry cell (new)
- A switch
- 7 connecting wires (3 wires with crocodile clip at one end and a long one to be attached to the jockey/crocodile clip)
- A mounted resistance wire on a metre rule (wire SWG 28)
(II) - A half-metre rule
- A knife edge (raised on a block of wood)
- A thread (approx. 20cm in form of a loop)
- A 50g mass
MOKASA JOINT EXAMINATION
232/3
PHYSICS
PRACTICAL
TIME: 2 ½ HRS
1. You are provided with the following;
 a rectangular glass block
 4 optical pins
 a soft board
 a plain paper
Proceed as follows:
(a) Place the glass block on the plain paper with one of the largest face upper most. Trace round the glass block using a pencil as
shown below.
A
P1
P2
i
B
b
r
L
c
P3
P4
D
eye
(b) Remove the glass block and construct a normal at B. Construct an incident ray AB of angle of incidence, i = 200.
(c) Replace the glass block and trace the ray ABCD using the optical pin
(d) Remove the glass block and draw the path of the ray ABCD using a pencil. Measure length L and record it in the table
below.
Page | 28
232/1,232/2,232/3 physics
0
Angle i
2
L (cm)
2
2
L (cm )
(
20
30
40
50
60
70
)
Sin i
0.1170
0.2500
0.4132
0.5868
0.7500
0.8830
(6 marks)
(e) Repeat the procedure above for the angles of incidence given.
1
(f) Calculate the value of L2 and ; Record in the table.
(g) Plot a graph of
(h)
1
(y-axis) against Sin2 i .
(3 marks)
Given that the equation of that graph is: :
(i)
(j)
(k)
2.
(a)
(5 marks)
1
1
1
1
Determine the – intercept C and the Sin2 i – intercept B.
C = _______________________________________
B = _______________________________________
Calculate the value of Q given by;
(1 mark)
(1 mark)
(2 marks)
( )
Hand in your constructions on the plain paper together with the answer script.
I. You are provided with the following:
 A voltmeter
 An ammeter
 A dry cell
 A cell holder
 A switch
 7 connecting wires (4 wires with crocodile clips at one end)
 A mounted resistance wire.
Connect voltmeter across the dry cell on an open circuit. Measure its e.m.f.
(2 marks)
V
E = ____________________________________
(b)
(1 mark)
Now connect the apparatus provided as shown below.
V
K
A
Mounted resistance wire
A
B
L
Crocodile clip
Page | 29
232/1,232/2,232/3 physics
Place the crocodile clip/jockey on the wire AB starting with L = 20 cm. Close the switch K. Record the terminal p.d. , V
and corresponding current I. Repeat for other values of L shown and complete the table.
Length L (cm)
Terminal p.d.
V(V)
Current
I (A)
(
1
)
(
1
)
20
30
40
50
60
70
1
(c)
(d)
(e)
2.
II.
(a)
(6 marks)
1
Plot a graph of (y-axis) against .
(4 marks )
1
1
1
Given that the equation of graph is;
Determine from the graph:
1
(i)
the intercept C on - axis
C = _________________________________
and hence calculate the e.m.f. E of the cell.
(ii)
the slope S of the graph.
(i)
Use the values of C and S above to find W,
given by
(ii)
What is the physical meaning of W.
You are provided with the following;
 Half-metre rule
 Knife edge (raised)
 A thread (approx. 20cm in form of a loop)
 50g mass
Determine the c.o.g of the half-metre rule.
c.o.g. = _____________________ cm mark.
(1 mark)
(2 marks)
(2 marks
(1 mark)
(1 mark)
(1 mark)
(b)
50cm
15 cm
0
d1
d2
c.o.g
Knife edge
50g
mass
(i) Pivot the rule at 15cm mark and balance it with the mass as shown. When it is well balanced, note and record the
position of the 50g mass;
(1
mark)
Position of 50g mass = _________________ cm mark
(ii) Use your results to determine the weight of the rule.
(2 marks)
Page | 30
232/1,232/2,232/3 physics
MOKASA JOINT EXAMINATION
1.
232/1
Physics
Paper 1
March / April 2016
Marking Scheme
Section A (25Marks)
Sleeve scale = 17.50mm
Thimble scale = 29 X 0.01 = 0.29mm
= 17.50 + 0.29
= 17.79mm
= 1.779 X 10-2 m
2. Energy lost/used to lift the machine parts / Weight of machine parts
3. - Density of gases is lower than in liquids
-Intermolecular forces in gasesare weaker than in liquids.
- Kinetic energy of gas particles is higher than that of liquids
4. Rate of flow; a1 v1 = a2 v2
2
2
πX0.009 X 3=v2 XπX 0.005
-1
v2=9.72 ms
5. (a) (i) density
Increases
(1 mark
(ii) Mass
Remains constant
(1 mark)
(ii) volume
Decreases
(1 mark)
6.
At equilibrium, sum of clockwise moments = sum of anticlockwise moments
8N X 1m = X X1m
X = 8N
7. Sharp edged shoes exert high pressure on ice which lowers the melting point of ice.
Melted water below provides lubrication/ lowers friction hence skidding/ sliding occurs.
8. A small piston exerts high pressure transmitted to the larger/slave piston,
This produces a larger force in the slave piston.
9. 0------ 100 →
100 units
2 ------ 95 →
93 units
= 18.74 o C
1 unit
= 93/100 = 0.93 units
18 units
= 18 X 0.93
= 16.74
10. (a) V.R. = 5
Efficiency = M.A/V.R x 100
284
M.A. = /71 71N
= 4 / 5 x 100
= 4
= 80%
11. Heat increases the kinetic energy of molecules
This leads to increase in the distance covered my moving molecules, hence its length increases
Section B (55 Marks)
12. (a) Inelastic collision
(b) m1u1 + m2u2 = (m1 +m2)v
22
/1000X450 + 976/1000X 0= (976/1000 +26/1000)v
v =10.8ms-1
(c) V2 = u2 + 2 a s
0= 10.82 + 2 X a X 7.5
a = - 10.82/15
a =- 7.7776 ms-1
F = ma = 1 X -7.7776 ms-1
F = -7.7776 N
(d) F = µR = µ mg
=m a = µX 1 X 10
µ =1 X 7.776/ 10
µ =0.7776
13 (a) This is due to constant change in direction of body hence change in velocity is acceleration
(b) (i) ω = 2πf = 2 X 3.142 X 2
v = r ω = 0.5 X 12.567
v= 6.283ms-1
(ii) T = mv2/r - mg
= 40/1000 X 6.28322/0.5 - 40/1000 X 10
= 2.7583N
(d) Determine the maximum horizontal distance it travels from the breaking point
(2 marks)
R = ut
h
= ½ gt2
=
20
= 5t2
6.283 X 2
Page | 31
232/1,232/2,232/3 physics
2
t = 4
t = 2s →
= 12.566m
14. (a) The pressure in the pen is higher than that outside the pen (atmospheric pressure ).
This causes the ink to flow outwards due to difference in pressure.
(b) The figure below is a simple hydraulic machine used to raise heavy loads.
(i)
P = F/A
= 120/0.006 = 20,000Nm-2
(ii) F = P x A = 20,000 X 0.50
= 10,000N
(iii)
- Should be incompressible
- Should be non-corrosive
- Should have high boiling point and low melting point
(c) h1ρ1g =h2ρ2 g
1360 x 1.25 = (74 – x)/100X 13600
x = 61.5cm
15 (a) For a helical spring or any other elastic material, the extension of a string is directly proportional to the force applied, so
long
as the elastic limit is not exceeded
(b) (i) What is the spring constant of the spring?
(2 marks)
Gradient = (3– 1)/(12 – 4)
= 0.25Ncm-1
(ii) What force would cause two such springs placed side by side to stretch by10cm
(3 marks)
In parallel arrangement, k = 25 X 2 = 50 Ncm-1
F = k e = 50 X 0.1 = 5Ncm-1
16. (a) What is meant by specific latent heat of fusion of a substance?
(1mark)
The amount of heat energy required to change a unit mass of solid to liquid at constant temperature.
(b) (i) mass of condensed steam.
(1mk)
Mass of steam
= 156 - 145 = 11 g
(ii) Heat gained by water + heat gained by calorimeter = 0.085 x 4200 (48-20) + 0.06 X 390(48-20)
= 10,651.2 J
(iii) Heat lost by steam=Heat lost by condensing steam + heat lost by condensed steam
= 0.011 X Lv+ 0.011 X 4200 X (100 – 48)
= 0.011Lv+ 2,402.4
(iv) Heat lost by steam+heat lost by condensed water = heat gained by water + heat gained by calorimeter
0.011 XLv+ 0.011 X 4200 X (100 – 48) = 0.085 X 4200 (48-20) + 0.06 X 390(48-20)
Lv= 749,890.9091JKg-1
(v) There are no heat losses
There is no change in mass
17. (a) Mass
= density x volume
= 100 x 0.25 = 25g
(b) Upthrust = Weight of the liquid displaced
= 100/1000 X 1 x 10 = 1 N
(c) Weight of the cork = 25/1000 x 10= 0.25N
Minimum downward force required = 1.0 - 0.25 = 0.75 N
(d) Upthrust reduces
18. (a) The pressure of a fixed mass of gas is directly proportional to its absolute temperature provided volume is kept constant.
(b) i)
Sulphuric acid index
ii)
A drying agent
Indicate the volume of gas
iii)
The apparatus are set up as shown and the water bath heated
The temperature and volume /length of index is recorded at regular intervals of time
A graph of volume of versus absolute temperature is drawn and graph analysed.
a straight line cutting the temperature axis at about -273K is obtained; hence volume is directlyproportional to
absolute temperature.
(c) P1V1/ T1 = P2V2/ T2
1.5 X 105 X 1.6 / 285 = 1.0 X 103 X V2 / 273
V2 = 1.5 X 105 X 1.6 X 273 /(2.85 X 1.0 X 103)
= 229.89 m3
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232/1,232/2,232/3 physics
MOKASA JOINT EXAMONATION
232/2
PHYSICS
Paper 2
(Theory)
March 2016
Marking scheme
2 hours
1. a)
(b) Angle of incidence = angle of reflection = 00
2. Image increases
3. M =
=
=3
=3
h = 2 x 3 = 6 cm
4. Like pole repel while unlike pole attract
5. The keepers acquire opposite polarity and keep the dipoles in a closed loop retaining their magnetic strength.
6.
P
Q
7.
(a) A.copper
B.dilute sulphuric acid
(b) Plate A is covered with hydrogen gas bubbles insulating it (polarization is taking place)
Local action is taking place at the zinc plate
(c) Addition of potassium dichromate (depolarizer)
8. a) A-microwaves
C- X-rays
b) Heating e.g cooking, drying
In warming greenhouse , infrared photography and heat-seeking missiles.
9. V = fʎ ʎ= V/f
Range =
m = 0.0017 m to 17 m
10. In transverse wave particles oscillate perpendicular to the direction of wave travel whereas in longitudinal wave oscillate
parallel to the wave travel.
11. Period T = 0.8 x 10-3s therefore frequency = 1/T = 1250Hz
wavelength ʎ = v/f = 400/1250 = 0.32m
12. I =
1
= 7.5 A safest fuse = 10 A which is slightly above the operating current.
Page | 33
232/1,232/2,232/3 physics
13. (a)
(i)
(ii)
(b)




(c)
The pointer deflects to the left and then goes back to rest position (zero). Changing magnetic flux links the coil
inducing an e.m.f which causes current to flow making the pointer to deflect.
No deflection. There is change in magnetic flux, no induced e.m.f and hence no current.
Using a stronger magnet
Increasing the number of turns of the coil
Winding the coil on a soft iron core
Increasing the speed of rotation of the coil;;
(i)
Determine the efficiency of this transformer.
(3marks)
1
Vs =
= 500 V;
Power output = 500 x 0.95 = 475 W;
Efficiency =
x 100 = 95%;
(ii)
Explain why the efficiency is less than 100%.
 Flux leakage
 Hysteresis loss
 Heating due to eddy current
 Copper losses
14. (a)Apparent depth = 32.4 – 9.9 = 22.5 cm
n=
=
= 1.44;;
1
=
(2marks)
= 0.6944;
(b) This is the angle of incidence in the denser medium for which the angle of refraction in the less dense medium is 900.;
(c)
(i) n =
=
1
1
1
1
= 1.5;;
(ii) Sin c = =
= 0.6667 ;
C = 41.810;
1
15. (a) Ohmic conductor obeys Ohm‘s law/ forms straight line through the origin on V-I graph e.g copper, aluminium while nonohmic conductor doesn‘t obey Ohm‘s law and the graph of V-I is not a straight line through the origin e.g semi-conductor,
thermistor, bulb.
(b) i)
Rseries = 3Ω +5Ω = 8Ω Rparallel =
= = 1.6 Ω
total resistance = 1.6 + 0.7 x 2 = 3.0 Ω
ii) Total current It =
=
= 2A
Vparallel = 1.6 x 2 = 3.2 V
I3Ω =
= 0.4 A
iii) (I) 6.0 V
(II) 6.0 – 3.2 = 2.8 V
iv) Lost voltage is the energy used to drive electrons through the cell itself.
16.
(a) Soft iron
(b) The current flows through the solenoid; it is magnetized and attracts the soft iron armature.;
(c) The magnetized core attracts the soft iron armature. The pivot armature pushes the springy metal strip which joins
contact B and A.;;
(d)
(i) The core
(1mark)
It loses its magnetism;
(ii) Soft iron armature.
(1mark)
Soft iron goes back to its original position thus switching off the current in the circuit.;
(e) Give one other application of an electromagnet.
(1mark)
Electric bell, telephone receiver, moving coil loudspeaker and circuit breaker.
(f) State two ways in which an electromagnet could be made more powerful.
(2marks)
Using a soft iron core, increasing the current and
Increasing the number of turns;;
17. (a) This due to an electric wind set up by the high concentration of charge at the sharp point. Air is ionized and like charges
repel.
(b)
(i)
1μF +4μF = 5μF
Page | 34
232/1,232/2,232/3 physics
(ii)
(iii)
18. (a)
(i)
(ii)
(b)
Series = (5x5)/10 = 2.5μF;
Total capacitance = 2.5 +2 = 4.5 μF;
Total charge = 4.5 x 8 =36μC;;
Voltage =
;;
Used to diffract the light waves and provide coherent sources;
Dark fringes and bright fringes are seen. The central fringe is brightest while the intensity of the other fringes
decreases away from the central fringe. ;
Dark fringes are as a result of destructive interference while bright fringes are as a result of constructive
interference;
Figure 8, shows an object O placed in front of a diverging lens whose principle focus is F.
Figure 8
O
c)
F
Use the figure below to answer the questions that follows
Concave lens
Rays from a distant
object
(ii)
(iii)
Name the defect.
(1mark)
Shortsightedness /myopia;
On the same diagram, sketch the appropriate lens to correct the defect and sketch the rays to show the effect of the
lens.
Correct lens;
Correct rays;
Page | 35
232/1,232/2,232/3 physics
KEIYO SOUTH JOINT EXAMINATION 2016
1.
232-1
PHYSICS 1
(THEORY)
MARCH/APRIL. 2016
2 HOURS
SECTION A (25MARKS)
What is the reading on the vernier caliper shown in figure 1 below?
Figure 1
0
(1mark)
10
cm
0
2.
1
2
3
The figure 2 below show three wooden blocks resting on a flat surface. (They are of the same material).
Figure 2
20cm
3.
20cm
(i) Arrange them starting from the least stable.
(1mark)
(ii) State the factor that you have considered in 2(i) above.
(1mark)
The figure below shows a U-tube manometer containing a gas, mercury and water. Calculate the gas pressure acting on the
mercury. (Take atmospheric pressure to be 1.05 x 105 pa, density of mercury and water to be 13600kg/m3and 1000kg/m3
respectively).
(3mks)
25cm
Gas
4.
20cm
10cm
Water
Mercury
Figure 3 below shows water flowing through two sections A and B of a pipe having different cross-sectional area.
Figure 3
Water
B
A
5.
6.
7.
8.
9
Indicate and explain the water level in manometer B.
(2marks)
In a clinical thermometer state how the thermometer can be made.
(1marks)
a) Move sensitive
b) Quick acting
A balloon is filled with a gas which is lighter than air. It is observed to rise in air up to a certain height. State a reason why the
balloon stops rising.
(1mark)
1800cm³ of fresh water of density 1000 kg/m³ is mixed with 2200cm³ of sea water of density 1025 kg/m³. Calculate the
density of the mixture.
(3marks)
When temperature of a gas in a closed container is raised, the pressure of the gas increases. Explain how the molecules of the
gas cause the increase in pressure
(2marks
The figure below shows a flat bottomed flask containing some water. It is heated directly with a very hot flame
Page | 36
232/1,232/2,232/3 physics
Water
Hot flame
Explain why the flask is likely to crack
(2marks)
10. State two factors which affect the rate of diffusion in gases
(2marks)
11. The figure below show a uniform metre rule balanced when pivoted at the 30cm mark under the conditions of forces as
shown below.
R
0
10cm
30
70cm
P
A
100
B
50g
4.8N
Pivot
Calculate the weight W of the rule.
12. The figure below shows an inclined plane and a load of mass 15kg pulled by an effort of 100N.
(3marks)
100N
15kg
) 300
Find the efficiency of the machine
(3marks)
SECTION B ( 55 Marks)
Answer all the questions in this section in the spaces provided
13. the figure below shows a simple pendulum of length 80 cm. the pendulum bob whose mass is 50 g oscillates between points A
and B, through its rest position C. A and B are both 10 cm higher than C
C
A
(a) (i) indicate with an arrow, on the path ACB, B
the direction of the greatest velocity of the bob as it moves from A to B. (1mk)
(ii) State the form of energy possessed by the pendulum bob at point A
(1 mark)
(b) Determine
(i) The velocity of the bob at point C
(2 marks)
Page | 37
232/1,232/2,232/3 physics
(ii) The tension in the string as the bob passes point C
(2 marks)
(Take acceleration due to gravity g=10m/s2
(c) State two characteristics of perfectly inelastic collisions
(2 marks)
(d) A body of mass 4.0 kg held at a vertical height of 500cm is released to travel along a frictionless curved path as shown in the
figure below.
Mass = 4.0 kg
Mass =6.0 kg
The 4.0kg mass strikes body of mass 6.0kg at rest immediately it reaches the horizontal. The bodies stick together and
move in the same direction. Determine the velocity of the bodies immediately after collision.
(4 marks)
14. (a) Define the term heat capacity
(1mark)
(b) A block of metal of mass 150g at 100oC is dropped into a logged calorimeter of heat capacity 40Jk-1 containing 100g of
water at 25oC. The temperature of the resulting mixture is 34oC. (Specific heat capacity of water = 4200J/KgK)
Determine;(i) Heat gained by calorimeter
(2mks)
(ii) Heat gained by water
(1mark)
(iii) Heat lost by the metal block
(1mark)
(iv) Specific heat capacity of the metal block
(3marks)
(b) Differentiate between boiling and evaporation
(2mark)
15. a) State Hooke‘s law.
(2marks)
b) The graph shows how extension e of a helical spring varied with load, hanging on it. (cm)
Extension (cm)
5, 23.2
4,,18.5
3,,13.8
2,9.2
1,4.5
(i) Determine from the graph, the proportionality constant of the spring.
c) State three factors that affect the proportionality constant of a helical spring.
(3marks)
(3marks)
Page | 38
232/1,232/2,232/3 physics
d) Two spring Q and R have proportionality constants 20Nm-1 and 25Nm-1 respectively. Q weighs 0.2 N while the weight of R is
negligible. The two springs are arranged to support a load of 3.0N as shown in the diagram that follows.
R
Q
Determine the extension in
3.0N
i) Q
(2marks)
ii) R
(2marks)
16. (a) Define the term relative density
(1mark)
(b) The diagram below shows a wooden log 12m long, density 800kg/m3 and cross-sectional area 0.06m2floating upright in
sea
water of density 1.03g/cm3, such that a third of it is covered by water.
A= 0.06m2
(i) Determine the weight of the block
(ii) The up-thrust on the block
(iii) The minimum weight that can be placed on the block to just make it fully submerged
(c) The following set-up was then used by a student to determine the relative density of a cork
Cork
Sinker
water
Sinker
(3marks)
(3marks)
(2marks)
Cork
Water
During the experiment, the following measurements were taken:- Weight of sinker in water = w1
- Weight of sinker in water and cork in air = w2
- Weight of sinker and cork in water = w3
(i) Write an expression for the up thrust on cork
(1mark)
(ii) Write an expression for the relative density of the cork
(2marks)
17. (a) Distinguish between angular velocity and linear velocity.
(1marks)
(b) A pendulum bob is whirled with uniform speed in a horizontal circle of radius 20cm.The bob describes an arc of length
5cm within 15 seconds.
Calculate
i)
Angular velocity
(3marks)
ii)
The uniform speed of the bob along the circular path
(2marks)
iii) The frequency with the bob moves along the circular path
(2marks)
iv)
State why the bob is accelerating yet it moves with the uniform speed along its path
(1mks)
Page | 39
232/1,232/2,232/3 physics
KESO JOINT EXAMINATION-2016
Kenya Certificate of Secondary Education
1.
232/2
PHYSICS
PAPER 2
TIME: 2 HRS
SECTION A: (25 marks)
Answer all the questions in this section in the spaces provided.
Figure 1 shows a ray of light XY striking the mirror CD held at an angle of 1080 to mirror DE.
D
Y
108°
42°
C
Fig 1
X
2.
3.
4.
E
Complete the path of the ray XY and state the final angle of reflection.
(2 marks)
Complete the path of the ray XY and state the final angle of reflection
(3 marks)
(1 mark)
A negatively charged polythene rod is placed on a pan of electric balance. State and explain what happens to the balance
reading if a positively charged glass rod is brought closer to the polythene rod.
(2 marks)
The figure 2 shows a bar magnet. Point A and B are in front of the magnet.
Fig. 2
A S
N B
(2marks)
Magnetic field
On the axis provided, sketch a graph showing how the magnetic field strength changes from A to B.
B
A
5.
6.
Distance
Explain how an increase in temperature affects the speed of sound in air.
Figure 3 below shows two parallel light rays incident on a concave mirror.
C
Fig 3
7.
(1 mark)
F
concave mirror
Sketch on the same diagram the path of the rays after striking the mirror and show the image.
(2marks)
A wire of resistance 20Ω is connected to a battery of 12V. Determine the heat dissipated in the wire in one minute.
(3 marks)
Page | 40
232/1,232/2,232/3 physics
8.
9.
The figure 4 below shows an arrangement for lighting three lamps, A, B and C only one of which is controlled directly by the
switch.
Fig 4
(a) Which of the lamp is directly controlled by the switch?
(1 mark)
(b) Which lamps can be on at once?
(1 mark)
Plane water waves produced in a ripple tank are passed from a region of deep water into a region of shallow water. Figure 5
shows the top view of the tank.
Boundary
Fig 5
Deep water
Shallow water
State what happens at the boundary to.
(a) The frequency of the waves.
(b) The speed of the waves.
(c) The wavelength of the waves.
10. (i) Arrange the following waves in order of decreasing wavelength.
Infrared, X-rays, microwaves, yellow light, radio waves, red light.
(ii) State one application of infrared wave.
11. Using domain theory, explain the process of magnetization.
12. Figure 6 represents a pinhole camera.
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(1 mark)
(3 marks)
Fig 6
Sketch rays to show the formation of an enlarged image in the camera. Label both the image and the object.
(2 marks)
Page | 41
232/1,232/2,232/3 physics
SECTION B: (55 marks)
Answer all the questions in this section in the spaces provided.
13. (a) Two coins were placed at the bottom of two jars each containing a different clear liquid as shown in figure 7.
Fig 7
Jar P
Jar Q
Liquid A
Liquid B
Coin
Coin
The liquids in the two jars are at the same level. The coin in jar Q appears shallower than that in jar P. Explain. (2 marks)
(b) The figure 8 shows a ray of light incident on a water-air interface from a source 8m deep.
A
Air
52.5
Water
0
8m
B
Fig 8
(i) Ray A is observed to bend as it enters the air. Give a reason why this occurs.
(1 mark)
(ii) If the refractive index of water is 1.35, calculate the angle of refraction of ray A
(3 marks)
(iii) Find the critical angle of water.
(3 marks)
(iv) Give a reason why ray B is not travelling out of water.
(1mark)
(c) Figure 9 below shows a ray of light incident on a triangular prism and a white screen is placed in front of the prism.
white ray
Fig 9
screen
Complete the diagram to show the path followed by the ray up to the screen.
14. (a)Figure 10 shows a glass lens in air and its two focal points F1 and F2.
(2 marks)
Three rays of light pass through F1 to the lens, on the figure show the path followed by the three rays through the lens and
into the air.
(3 marks)
(b) I
State one possible cause of myopia.
(1 mark)
II. State the type of lens that is used to correct myopia.
(1 mark)
Page | 42
232/1,232/2,232/3 physics
(c) The figure 11 below shows a pin 60mm long placed along the principal axis of a lens of focal length 50mm. The near end of
the pin is 80mm form the lens.
principal axis
600mm
Fig 11
800mm
Determine the length of the image.
(4 marks
(d) In an experiment to determine the focal length of a converging lens several values of image distance and the corresponding
magnification were obtained. A graph of magnification m against image distance (V) was plotted as shown below.
From the graph determine the focal length of the converging lens.
15. (a) The following graph shows the potential difference, V against current, I for a certain device.
(4 marks)
4.5
4.0
3.5
P.d (v)
3.0
2.5
2.0
1.5
1.0
0.5
0
1.0
2.0
3.0
4.0
Current (A)
5.0
6.0
7.0
(i) State with a reason whether the device obeys Ohm's law.
(ii) Determine the resistance of the device when current is 1.0A.
(iii) State how resistance of the device varies as current increases from zero to 5.0A.
(1 mark)
(1 mark)
(1 mark)
Page | 43
232/1,232/2,232/3 physics
(b) When the switch S is kept open in the circuit shown in figure 12 the voltmeter reads 1.5V. When the switch is closed, the
readings drops to 1.3V and the current through the resistor is 0.5A.
V
S
R
(i)
(ii)
(iii)
16. (a)
Fig 12
What is the e.m.f of the cell?
What the terminal voltage of the cell?
Calculate the value of R.
Figure 13 shows a loudspeaker producing sound waves in air.
(1 mark)
(1 mark)
(2 marks)
X
X
Wave motion
Loud speaker Y
Fig 13
Y
X compressions
Y Rarefactions
(i) Explain how compression and rarefactions are formed.
(2 marks)
(ii) Show on the diagram the wavelength of the wave.
(1 mark)
(iii) The wavelength of the waves produced is 0.4m. Determine the frequency of the waves if the speed of sound in air is
330m/s.
(2 marks)
(b) In an experiment to observe interference of light waves a double slit placed close to the source as shown in figure 14 below
Fig 14
(i) What is monochromatic source
(1 mark)
(ii) State the function of the double slit.
(1 mark)
(iii) Briefly describe what is observed on the screen.
(1 mark)
(c) Briefly explain what is observed on the screen when
(i) The slit separation S1S2 is reduced
(1 mark)
(ii) White light source is used in place of monochromatic source.
(1 mark)
17. (a) In figure 15 below, a sharp pin is fixed on a cap of a leaf of electroscope. The electroscope is highly charged and then
left for
some time.
Fig. 15
Sharp pin
Charged electroscope
State and explain the observation made after sometime.
(b) Four capacitors were connected in a circuit as shown in figure 16. The switch is then closed.
(2marks)
Page | 44
232/1,232/2,232/3 physics
3V
Fig 16
2μF
2μF
3μF
3μF
Determine ;
(i) The effective capacitance
(3 marks)
(ii) The total charge
(3 marks)
(iii) The energy stored in the combination when the switch is closed.
(3 marks)
(c) Figure 17 below shows a pair of parallel plates of capacitors connected to a battery. The upper plate is displaced slightly to
the left.
Fig. 17
+
d
Suggest two adjustments that can be made so as to reduce the effective capacitance.
(2 marks)
Page | 45
232/1,232/2,232/3 physics
KEIYO SOUTH JOINT EXAMINATIONS (KESO) 2016
232/3
PHYSICS PAPER 3
CONFIDENTIAL









QUESTION 1
Each candidate requires the following:
One complete retort stand.
An optical pin.
A bare copper wire, 15cm long and 1.2mm in diameter.
A protractor.
Two pieces of plasticine (about 10g each)
Rubber (cork) stopper to fit a conical flask.
A stopwatch
A vernier caliper.
A beam balance.








QUESTION 2
Each candidate requires the following:
One 10 carbon resistor labeled R.
A nichrome wire, 100cm long labeled W mounted on millimeter scale (SWG 32) labeled AB.
One new size D dry cell and a cell holder.
One jockey.
One centre zero galvanometer.
Eight connecting wires, four with crocodile clips at both ends.
A micrometer screw gauge.
A switch.
Page | 46
232/1,232/2,232/3 physics
1.
2.
3.
4.
5.
6.
7.
KEIYO SOUTH JOINT EXAMINATION 2016
PHYSICS
PAPER 1
MARKING SCHEME
SECTION A (25MKS)
0.5 + (5 x 0.01) = 0.55cm 
(i)
I, III, II 
(ii)
Position of centre of gravity. 
Pg = Pa + Pw + Pm , 
= Pa + hpa(w) + phg(w) ½
= 1.05 x 105 + 0.25x 1000 x 10 + 0.1 x 13600 x 10
121100NMˉ² 
Lower than A. 
At A there is higher velocity and therefore lower pressure.
(a)
Making the capillary bore more narrower. (1/2)
(b)
Making the bulb thinner. (1/2)
upthrust is equal to the weight of the balloon
Density of mixture
=
Max of mixture
Volume of mixture
Total volume = 180 + 2200 = 4000cm³
Mass of fresh water =
x V = 1000 x 1800 = 1.8kg
1000,000
Mass sea water
x V = 2025 x 2200 = 2.255kg
1000,000
Total mass
=
1.8 + 2.255
=
4.055kg
Density of mixture
8.
9.
10
11.
12.
-
Total mass of mixture
Total volume mixture
=
4.055
4000 x 10ˉ6
=
1012.75kg/m³ or 1.013g/cm³
Speed of molecules increase/ k.e increase/molecules move fast
Glass is a poor conductor of heat, uneven/unequal distribution of heat causes cracking
(do not accept for non uniform distribution of heat)
Density 
Temperature 
Taking moments about the pivot point P
Sum of clockwise moment = W x 20 + 0.5 x 40
Sum of anticlockwise moment = 4.8 x 20
20W + 20 = 96
20W = 76
W = 3.8N
M.A = =
Eff =
1
1
=
= 1.5
x 100
=
1
x 100
= 75%
SECTION 3 (55MKS)
13. (i) arrow horizontal line and straight line at point C
(ii) potential energy/ potential/ P.E
b) i)
P.E= K.E
Mgh= ½ mv2
V=√2x10x0.1 =(√2)
V = 1.41m/s
ii)
t = mv2/r +mg
= 0.005/8x2+0.005x10
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232/1,232/2,232/3 physics
=0.0625 N
(c) The total mass is the sum of the masses of the individual bodies
The bodies end up with a common velocity
1
(d) At the bottom of fall mv2 = mgh
1
=√
=√
-1
= 14.14ms
Momentum before collision = mv
= 4kg x 14.14ms-1 = 56.57 kgms-1
Momentum after collision
= (m + m1)v1 = 10kg x v1
Momentum before collision = momentum after collision
56.57kgms-1 = 10kg x v1
v1 = 5.657ms-1
14. (a) The quantity of heat required to raise the temperature of a given mass of a material by one Kelvin.
(b) (i)
C = Q

Q = C
= 40 x (34-25)
= 40 x 9 = 360J
(ii) MwCwD = (0.1 x 9 x 4200) = 3780J
(iii) Heat lost = heat gained by calorimeter + heat gained by water
= 3780 + 360 = 4140J or 4.14KJ
(c) 150 x Cm x  = 4140
1000
0.15 x (100 – 34) Cm = 4140
9.9C = 4140
Cm = 4140 = 48.18JKg-1K-1
9.9
(d)
Boiling
Evaporation
- Temperature is constant
- Temperature can vary
- Affected by impurities and pressure
- Not affected with impurities
- vigorous with bubbles
- not vigorous, no bubbles
- takes place in the whole liquid
- takes place at the surface
V
14.
(a) For a helical spring or other elastic material, the extension is directly proportional to stretching force
provided the elastic limit is not exceeded.
(b) 21.5 ± 0.1Nm-1
(c)
- Diameter of spring √1mk
- Length of spring √1mk
- Thickness of the wire coiled to make the spring √1mk
- Material used to make the spring
(d) (i) e = f/k
= 3.0/20 √1mk = 0.15m √1mk
3.2
(ii) e = /25√1mk = 0.128m √1mk
15. (a) It is the number of times a substance is denser than an equal amount of water
(b) (i) Weight = mass x gravity weight of water displaced
p=M
V
M =pxV
= (800 x 12 x 0.06)
W = Mg = 576Kg x 10 = 5760N
(ii) Uptrhust = Weight of liquid displaced
= p 2 x Vl x g
= 1.03 x 103 x 0.06 x 4 x 10
= 2472 N
(iii) 5760 – 2472
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232/1,232/2,232/3 physics
c.
= 3288N
(i) (W2 – W3)
(ii) R.d = weight of cork in air
Weight of equal vol. of water
=
W2 – W1
W2 – W3
16
Angular velocity is the change in angular displacement per unit time (rate of change of angular displacement
with time) while linear velocity is change in linear displacement with time (rate of change of linear
displacement with time ) ;
b) (i) θ=s/r=0.05
ALT
a= θ , θ = s ; both
A= θ
t
r
t =0.25
a = s = 0.05 ;
15; fors
rt 0.2x 15
(ii)
a = v = v rw
r
= 0.2 x 0.01667 ; formula or substitution
= 0.00334 m/s ; ANS ( 3.334 x 10 -3 ms-1)
(iii)
a = 2nf = f = a
2II ; formula or substitution
= 0.01667
2x3 .142
= 2.653 x 10-3 Hz; Ans
(i) The direction of motion of the ball changes continuously/ velocity changes in direction throughout;
1
3
2
2
1
Page | 49
232/1,232/2,232/3 physics
KEIYO SOUTH SUB-COUNTY SECONDARY SCHOOLS MOCK 2016-(KESO)
Kenya Certificate of Secondary Education
PHYSICS
PAPER 2
MARKING SCHEME
D
1.
108°
Y
42°
42° 48°
30°
48°
60°
C
60°
X
2.
3.
E
- Correct direction of two reflected rays
- Final angle of reflection = 60o
It has a higher electromotive force.
Cheaper.
Any one;
(b) This is due to force of attraction between the charged rods (unlike charges);
4.
ReducIng strength from A ;
Increasing strength towards B ;
Deny 1mark if graph touches horizontal axis
Magnetic
field
strength
O
A
5.
6.
Distance
B
Increases speed of sound in air ; due to decrease in its density.
Both rays correctly reflected;
F
C
Both rays correctly reflected ;
Diminished image at F ;
Diminished image at F;
V 2t
R
12)2 x1x60s
=
20
7.
H=
= 432 joules ;
8.
(a)
(b)
9. (a)
(b)
(c)
10. (a)
(b)
Lamp B ;
B and C ;
no change in frequency ;
Wave length decreases;
Velocity of the wave decreases;
Radio wave, microwaves, infrared, red light, yellow light, x-ray.
- Cooking/ Heating/ Drying.
- Warming greenhouses in Agriculture.
- Infrared photography.
- Heat-seeking missiles.
11. Every magnetic material consist of tiny particles known as dipoles ; magnetization involves aligning the diploles to face
one direction ; When all diploes face one direction, no further magnetization can be added;(magnetic saturation).(wwtte)
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232/1,232/2,232/3 physics
12.
SECTION B
13. (a)Liquid B has a higher refractive index than liquid A ; hence refracts the light more as it enters air ; its vise versa for
liquid A
(i)
 there is change in optical density of medium
 change in velocity of light as it moves from water to air
(ii)
0
1
(iii)
1
1
1
(iv)
b)
C = 47.7950
The critical angle of water has been exceeded
white ray
screen
14. (a)
(b)
I
II
Each correctly drawn ray ;
-Crystalline lens has a short focal length ;
- The eye ball is too long;
Any one ;
Diverging lens / concave lens ;
Page | 51
232/1,232/2,232/3 physics
c)
1
1
1


u
v
f
1
1
1
3



v
50
80
400
400
v 
3
u  80  60  140
1
9

v
700
700
v 
9
;
;
;
length of image =
400 700

3
9
 55.56mm
m
;
V
2.0  1.0
=
;
30  20
1
=
;
10
V
1
From the equation m =
f
1
f
1
1

Hence
and
f 10
;
f = 10cm ;
Page | 52
232/1,232/2,232/3 physics
15. (a) i)
Does not obey ; Graph is non-linear and does pass through the
Origin ;
ii)
When I = 1.0A , V = 2.0V
V
I
2 .0
=
= 2.0Ω ;
1 .0
R=
(b)
16.
(a)
iii)
(i)
(ii)
Resistance reduces ;
1.5V ;
1.3V
(iii)
R=
V
I
1.3V
=
;
0 .5 A
= 2.6Ω ;
Compression - particles of air are clear than normal creating a region of high pressure
Rarefaction - Particles of air are further apart than normal creating a region of low pressure;
(ii) Length occupied by one compression and rarefaction
(i)
v
(b)
(c)
17. (a)
(b)
330
f 

 825Hz
(iii)

0.4
(i) monochromatic source is a source of light that produces only on colour of light 
(ii) To act as two sources of light which are coherent 1
(iii) Bright bands and dark bands are observed1
(i) The band separation also reduce
(ii) Coloured bands (spectrum of white light/rainbow colours) are observe
The leaf falls ¹; the sharp pin discharges the electroscope by concentration of charges at sharp points.
(Charges concentrate at a sharp points causing discharge).
(i) Series
1/CS1 = 1/C1 + 1/C2
1/CS2 = 1/C1 + 1/C2
=
1 1

2 2
CS = 1 µF;
(ii)
(iii)
c)
1 1

3 3
3
=
µF ;
2
=
CS2
Parallel CT = C1 + C2
= 1 + 1.5
= 2.5 µF;
Q = CV;
= 2.5 X10-6F X 3.0V;
= 7.5 X 10-6C;
1
CV2
2
1
= X 7.5X10-6 µFX (3.0V)2
2
W =
= 3.375X10-5Joules.
Reducing the area of plates.
Increasing the distance d (separation distance)
Page | 53
232/1,232/2,232/3 physics
KUWED JOINT EXAMINATION COUNCIL
1.
2.
3.
4.
Velocity (m/s)
5.
Kenya Certificate of Secondary Education
232/1
PHYSICS
PAPER 1
(THEORY)
JULY/AUGUST 2016
TIME: 2 HOURS.
SECTION A (25 MARKS)
State the name of the instrument used to take the following readings;
(i) 10 kg
(1 mark)
(ii) 0.00245m
(1 mark)
A micrometer screw gauge which had an error of +0.02mm was used to measure the diameter of a spherical marble. If the
actual diameter was 3.67mm, draw a micrometer screw gauge showing its reading.
(2 marks)
Fifty drops of oil have a volume of 1.0cm3. If a drop of oil forms an oil patch of diameter 20cm, determine the size of the oil
molecule.
(2 marks)
(a) A gun when fired the firer experiences equal backward recoil, explain.
(1 mark)
(b) A man whose mass is 80kg stands on weighing machine. When the lift ascends with an acceleration of 2.45m/m 2, what is
(2 marks)
The figure below shows a sketch graph of velocity-time graph for a body falling through a liquid. Explain the motion of the
motion between.
A
6.
7.
8.
C
D
B
Velocity (m/s)
(a) B and C
(1 mark)
(b) A and B
(1 mark)
(c) C and D
(1 mark)
In a faulty mercury-in-glass thermometer it was found that the mercury level stands at 2 cm mark in the tube at 00C and 20cm
when in steam above boiling point water at normal atmospheric pressure. Calculate the temperature when the mercury stands
at 13cm mark.
(2 marks)
A balloon with argon gas of volume 199cm3 at the earth‘s surface where the temperature is 210C, and the pressure 760mm of
mercury. If it is allowed to ascend to a height where the temperature is 2 0C and the pressure 100mm of mercury, calculate the
volume of the balloon.
(2 marks)
(a) The spiral springs shows in the figure below are identical. Each spring has a spring constant K = 200N/m. Each rod
weighs 0.1N and each spring weigh 0.1N.
150N
Determine the total extension caused by the 150N weight.
(b) Apart from length of the spring and nature of material, state one other factor affecting the spring constant.
(2 marks)
(1 mark)
Page | 54
232/1,232/2,232/3 physics
9.
The figure below shows a cuboid in two positions. Explain how the stability of the cuboid changes when it is changed from
position ‗a‘ to ‗b‘.
(2 marks)
(a)
(b)
10. (a) How does the area of support affect the stability of a body?
(1 mark)
(b) The figure below shows a uniform rod AE which is 40cm long. It has a mass of 2kg and pivoted at D. If 2N is acting at
point
E, and 30N force is passed through a frictionless pulley.
10cm
A
10cm
E
D
X
2N
Find the force X acting at end A.
(3 marks)
SECTION B (55 MARKS)
Attempt all the questions in this section
11. (a) Sketch a block and tackle pulley with three movable pulleys in the lower block and two fixed pulleys in the upper block,
to give a velocity ratio of 6.
(3 marks)
Find:
(i) An effort of 450N is used to raise a load of 2700N. Determine:
(2 marks)
 Efficiency of the pulley system.
(2 marks)
(ii) If all the wasted energy is used to raise the lower block and the frictional force between pulleys and moving parts is
3.6N; determine the weight of the lower block.
(2 marks)
(c) If the load moved through a distance of 50cm, determine the useful work done by the effort.
(3 marks)
(d) James applied a force of 400N in pushing a stationery wall. If he took one hour to push the wall, calculate the power
developed.
(1 mark)
12. (a) The figure below shows dots which were made by a ticker timer – tape attached to a trolley. The trolley was moving in
the direction shown.
A
B
C
If the frequency used was 60Hz, distance AB = 12cm and BC = 7.2cm, determine
The velocities between AB and BC
(2 marks)
The acceleration of the trolley.
(2 marks)
An object is projected horizontally with a velocity of 40m/s at the top of a cliff 100m from the ground. (Take g = 10m/s 2)
Calculate the time taken for the object to hit the ground
(3 marks)
What is the range of the object from the foot of the cliff
(2 marks)
State two assumptions that were made when deriving the equation of continuity?
(2 marks)
A ship made of steel is able to float while a steel rod sinks explain.
(1 mark)
A block of length 50cm, cross-sectional area of 5cm2 and density 1.4g/cm3 is completely immersed in a liquid of density
1.08g/cm3 find
(i) the mass of the block
(2 marks)
(ii) the weight of the block in the liquid.
(2 marks)
(iii) the apparent loss in weight of the block if three quarter of it is immersed in the liquid.
(2 marks)
14. (a) Define specific latent heat of fusion
(1 mark)
(b) Given the following. A filter funnel, a thermometer, a stop watch, ice at 0 0C, an immersion heater rated P watts, a beaker,
a stand, boss and clamp and weighing machine.Describe an experiment to determine the specific latent heat of fusion of ice.
Clearly state the measurements to be made.
(4 marks)
(i)
(ii)
(b)
(i)
(ii)
(b)
13. (a)
(b)
Page | 55
232/1,232/2,232/3 physics
0
(c) 200g of ice at 0 C is added to 400g water in a well lagged calorimeter of mass 40g. The initial temperature of the water
was 400C. If the final temperature of the mixture is X0C, (Specific latent of fusion of ice L = 3.36 x 10 5JKg-1, specific heat
capacity of water, c = 4200Jkg-1K-1, specific heat capacity
of copper = 400Jkg-1K-1)
(i) Derive an expression for the amount of heat gained by ice to melt it and raise its temperature to X 0C
(2 marks)
(ii) Derive an expression for the amount of heat lost by the calorimeter and its content when their temperature falls to X0C.
(2 marks)
(iii) Determine the value of X.
(3 marks)
15. (a) The moon goes round the earth at constant speed. Explain why it is true to say that the moon is accelerating. (1 mark)
(b) A string of negligible mass has a bucket tied at the end. The string is 60cm long and the bucket has a
mass of 45g. The bucket is swung horizontally making 6 revolutions per second. Calculate:
(i) The angular velocity.
(1 mark)
(ii) The centripetal acceleration.
(2 marks)
(iii) The tension on the string.
(2 marks)
(iv) The linear velocity.
(1 mark)
(c) Figure 6 shows of mass m = 200g attached to the centre of a rotating table with a string. The radius of the spring was
varied and different values of angular velocity recorded. The mass of the body remained constant throughout the experiment.
r
String
Figure 6
The results obtained for angular velocity and radius were used to plot the following graph.
From the above graph;
(i) Calculate the value of the slope.
1
(ii) If 2 and are related by the equation;
(iii) State the significance of P.
1
find the value of P.
(2 marks)
(2 marks)
(1 mark)
KUWED JOINT EXAMINATION COUNCIL
Kenya Certificate of Secondary Education
Page | 56
232/1,232/2,232/3 physics
1.
2.
3.
4.
5.
6.
7.
8.
9.
232/2
PHYSICS
PAPER 2
(THEORY)
JULY/AUGUST 2016
TIME: 2 HOURS.
SECTION A (25 MARKS)
State one difference between an image formed by a pinhole camera and the viewed through a magnifying glass.
(1 mark)
Distinguish between longitudinal and transverse waves giving one example of each.
(3 marks)
An electric immersion heater rated 240V, 3kW is to be connected to a 240V mains supply, using a 10A fuse. Showing your
working, state whether the fuse is suitable or not for circuit.
(3 marks)
Complete the following table
(2 marks)
Source
Detector
Application
Communication
Hot body
Drying clothes
State one defect of a simple cell and explain how it can be minimized.
(2 marks)
A wire of resistance 27 ohms is cut into three equal lengths. If the three wires are connected in parallel, what is the effective
resistance?
(2 marks)
A ray of light makes an angle of 35 0 with the glass surface. Calculate the total distance the ray covers through a glass of
refractive index 1.45, given that the width of the glass is 6cm.
(3 marks)
State one application of each the following mirrors.
(2 marks)
(i) Convex mirror
(ii) Parabolic reflector
K
B
𝑔𝑎𝑚𝑚𝑎
(ii) Determine the values of x and y
10. Explain briefly how a p-type semiconductor is made.
11. Figure 1 represents a displacement – time graph for a wave.
(1 mark)
(2marks)
(1 mark)
Determine the frequency of the wave.
(3 marks)
SECTION B (55 MARKS)
12. (a) The two free ends of a coil are connected to a center – zero galvanometer. When the north pole of magnet is moved
towards the coil, the pointer deflects in the direction shown in figure 2.
Figure 2
State with a reason the behaviour of the pointer inn the following cases:
(i) The north pole of the magnet is held stationary near P.
(2 marks)
(ii) The north pole of the magnet is made to approach the coil from end Q
(2 marks)
(b) State Faraday‘s law of electromagnetic induction.
(1 mark)
(c) A transformer supplies 12V when it is connected to 240V supply of electricity. The output of the transformer is
connected to 12V 36W bulb. The current drawn from the supply by the transformer is 0.5A. Calculate:
(i) the input power of the transformer.
(3 marks)
(ii) the current drawn from the transformer.
(3 marks)
(iii) The output power of the transformer.
(1 mark)
(iv) the efficiency of the transformer
(3 marks)
Page | 57
232/1,232/2,232/3 physics
13. (a) Draw the electric field pattern in figure 3
Figure 3
+
(3 marks)
+
+
+
(b) Figure 4 shows a system of capacitors connected to 100V supply.
Figure 4
Determine:
(i) the value of a capacitor for the whole circuit system.
(ii) the charge through the 6F capacitor.
(iii) the p.d across of the 8F capacitor.
(c) State two factors that affect the capacitance of a parallel plate capacitor.
14. (a) Figures 5(a) and 5(b) shows ultra violet radiation striking polished zinc plates placed on negatively
charged
gold leaf electroscopes respectively.
(3 marks)
(3 marks)
(4 marks)
(2 marks)
and positively
Explain why the leaf collapses in fig (a) but does not collapse in fig (b)
(4 marks)
(b) (i) State two factors which determine the speed of photoelectrons emitted from a metal surface.
(2 marks)
(ii) In an experiment using a photocell, u.v. light of varying frequency but constant intensity was made to strike a metal
surface. The maximum kinetic energy (K. E. max) of photoelectrons for each frequency, f, was measured.
The graph in figure 6 shows K.E.max varies with f.
Given K.Emax = hf - , from the graph, determine the values of:
(a) The h (planks constant)
(3 marks)
(b) The from the graph.
(3 marks)
(c) Light of frequency 5.5 x 1014 Hz is made to strike a surface whose work function is 2.5Ev. Show that photoelectric effect will
not take place. (Use the values of h from (b) above.
(Take e = 1.6 x 10-19C)
(3 marks)
15. (a) You are provided with a 12V a.c. source, four diodes and a resistor.
(i) Draw a circuit diagram for full wave rectifier and show the points at which the output is taken.
(5 marks)
(ii) Sketch a graph of voltage against time before rectification.
(1 mark)
(iii) Sketch a voltage – time graph after rectification.
(1mark)
(iv) Sketch a voltage – time graph after rectification with a capacitor connected across the resistor in (i)
(1 mark)
(b) A radioactive sample of half life 130 days initially has 1.0 x 10 20 radioactive atoms. Determine
the number of radioactive atoms that would have decayed after 390 days.
(3 marks)
Page | 58
232/1,232/2,232/3 physics





















1.
KUWED JOINT EVALUATION TEST 2016
PHYSICS PAPER 232/3
PRACTICAL
CONFIDENTIAL
Question 1
The apparatus required by each candidate are
One jockey/ or crocodile clip
Two new dry cells (size D)
An ammeter 0 – 1A
A voltimeter 0 – 5A
One cell holder (2 cells)
One switch
Six connecting wires, at least three with crocodile clips at one end
Nichrome wire of gauge SWG 32 mounted on a meter rule
Question 2
Metre rule
A candle
A metre rule
White screen
Lens holder
Biconvex lens of focal length 20cm
Match box (to be shared)
On 100g mass labelled R.
10g masses
One complete retort stand
Cellotape
Weighing balance C to be shared
KURIA WEST SUB-COUNTY JOINT EXAMINATION COUNCIL 2016
232/3
PHYSICS
PAPER 3
PRACTICAL
JULY/AUGUST 2016
TIME: 2½ HOURS.
You are provided with the following
 One jockey or crocodile clip
 Two new dry cells (size D)
 An ammeter 0 – 1A
 A voltimeter 0 – 5V
 A cell holder
 Switch, S
 Six connecting wires atleast three with crocodile clips at one end.
 A resistance wire mounted on a mm scale
(a) Proceed as follows
Set up the circuit asS show in fig. 1 below.
Figure 1
A
V
A
L
B
Resistance wire
Page | 59
232/1,232/2,232/3 physics
(b) Close the switch and place the jockey in contact with the resistance wire such that the length, L of the wire = 0.10m.
Measure and record the current, I, through the wire AB and the potential difference, pd, V across it. Record your results
in table 1 below.
L (m)
0.1
0.3
0.5
0.7
0.9
p.d V
I (A)
R = ( )
(A-1)
(7 marks)
(c) Repeat procedure (b) above for the other values of L given in the table 1 above. Read and record the corresponding
values of I and V in table 1 above.
1
(d) Plot a graph of against R.
(5 marks)
(e) Determine the slope, S of your graph
(3 marks)
1
(f) Given that
, determine the value of
(i) E
(3 marks)
(ii)
(2 marks)
PART 2
2. You are provided with the following:
 A candle
 Metre rule
 White screen
 Lens holder
 Convex lens
 Match box (To be shared)
Proceed as follows
(a) Place the lens on a metre rule. Arrange the set up as shown below fig 2.
u
Flame
v
Lens
White screen
Candle
Lens holder
Metre rule
Figure 2
(b) Adjust the position of the lens so that it is a distance u = 30cm from the candle. Adjust the position of the screen until a well
focused image of the flame is formed on the screen.
Measure and record in the table 2, the image distance v, between the screen and lens.
(c) Repeat part (b) for other values of (u) shown in the table 2 and complete the table.
u (cm)
30
35
40
v (cm)
x=
y=
(
1)
(cm)
(d) Determine the mean value of y
PART B
You are provided with the following:
 Metre rule
 Cellotape (To be shared)
 Complete retort stand.
 Weighing balance
 Masses

(e) Arrange the apparatus as shown in fig. 3
(2 marks)
(1 mark)
Page | 60
232/1,232/2,232/3 physics
Clamp
Retort stand
1cm L1
M
L2
Metre rule
R
Adjust the metre rule until it balances horizontally when there is no mass hanged on it. Record the position of the centre of
gravity (c.o.g)
Centre of gravity, C ____________________ cm mark.
(1 mark)
(f) Fixed mass R at the end of the metre rule using a cellotape. This mass should remain fixed through the experiment.
(g) Hang 10g mass m on the metre by use of the thread at 1cm mark. Adjust thread T until the metre rule balances again at a new
mark. Record the length L1 and the corresponding L2 in the table 3 below.
(h) Repeat the procedure (h) for the other masses as in the table 3 below.
Mass m (g)
10
20
30
40
50
60
Weight of m w (n)
L1 (cm)
L2 cm
y = (c – L2)p (kgcm)
x = L2 – WL1
(i) Measure the mass of the metre rule.
Mass of metre rule (p) _________________ kg
(j) Plot a graph of y against x
(k) Calculate the slope S of the graph.
(1 mark)
(5 marks)
(3 marks)
Page | 61
232/1,232/2,232/3 physics
KUWED EXAMINATION COUNCIL 2016
PHYSICS PAPER 232/1
PAPER 1
MARKING SCHEME
1.
2.
3.
(i) Beam balance
(ii) Micrometer screw gauge
= 3.67
0.02 (1 mk)
3.69
Volume of one drop =
V=Axh
V=
V ]=
1
(1 mark)
(1 mark)
= 0.02cm3  1mk
1
4.
5.
6.
7.
h=
1
1
h = 6.3336cm  1mk
(a) This is due to Newton‘s third Law of motion. The gun exerts an equal backward force the person
holding it. (Action and reaction forces are equal and act in opposite directions.
(b) Reading = m (g + a)  1mk
= 80 (10 + 2.45)
= 996.0N  1mk
(a) The body moves with a decreasing acceleration.  1mk
(b) The body moves with constant velocity/the body has zero acceleration.  1mk
100
20
x
13
0
2
1
 1mk
1
1
1
1
1
800 = 1800 – 18x
18x = 1000
x = 55.560C  1mk
V1 = 199
Tt = 294
P1 = 76mHg
T2 = 275
P2 = 100mHg
 1mk
1
8.
1
V2 = 1414.65cm3  1mk
(a) F = Ke
e1 =
1
 1mk
1
1
e2 =
= 0.3753m
Total e = e1 + e2 = 0.62597m  1mk
(b)  Thickness of the wire
 Number of turns per unit length
 Diameter of the spring
Any one  1mk
9.  The stability increases  1mk
 The centre of gravity position is lowered closer to the ground.  1mk
10. (a)  The stability increases with increase in area of support. Or
 Decrease in area reduces the stability of the body 
Page | 62
232/1,232/2,232/3 physics
(b) F1d1 = F2d2 (clockwise movement equals to anticlockwise movements)  1mk
(x x
(
1
0.3x = (6.2 – 2)
x = 14N  1mk
1
1
)
(
1
)
(
1
1
)  1mk
11. (a)
E
 Correct strings flow  1 mk
 Labeling of load and effort  1 mk
 Workability  1 mk
(i)  M.A. =
2 mks
E =
 1 mk
 1 mk
(ii) Frictional force + wasted effort = Weight of lower block
= 3.6 + 0 = 3.6N
The machine is 100% efficient.
No wasted effort
(c) Loud x Load distance = 2700 x 0.5 = 1350J
(d) Power =
=
= 0J
1
1
12. (a) (i) T =
VAB =
VBe =
1
(
(
1
–
(ii) Ace =
(
1
 1 mk
1
1
)
)
 1 mk
 1 mk
=
= 2294.51cm/s2  1 mk
(b) (i) V = u + at; S = ut + ½ at2, g = 10  1 mk
100 = 0 + ½ x 10 x t2  1 mk
t2 = 20
t=√
t = 4.472s  1 mk
(ii) Range = V x time  1 mk
= 40 x 4.472
= 178.885m
(c)  The fluid in non-viscouse  1 mk
 The fluid is incompressible  1 mk
 The flow is steady/streamlined  1 mk Any 2
13. (a) The ship displaces a large amount of weight of the fluid since it is hollow while the rod is not hollow therefore displaces
with weight of the fluid.  1 mk
(b) (i) V = Ah = 5 x 50 = 250cm3  1 mk
m = f x v = 250 x 1.4 = 350g – 0.35kg  1 mk
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232/1,232/2,232/3 physics
-1
(ii) Weight = mg (g = 10Nkg )  1 mk
= 0.35 x 10 = 3.5N
U = Pvg = 1080 x
1
Weight fluid = 3.5 – 2.7 = 0.8N
(iii) Volume displaced = 50 x 5 x ¾ = 187.5cm3
1
1
1
Weight fluid =
= 2.025N up thrust  1 mk
1
Apparent loss = 3.5 – 2.025 = 1.475N  1 mk
14. (a) Quantity of heat required to convert a unit mass of a solid to a liquid at constant temperature.  1 mk
(b) - Weigh the empty beaker
- Switch the heater on for a time t collect melted ice and record the mass m1
- Mass of melted ice = m1 – m0
- The quantity of heat = (m1 – m0)L = Pt
L=
Stop clock
Ice
Melted ice
Beam balance
(c) (i) Q = ml + Mc    1mk
=(
)
(
)
1
1
= 6.72 x 104 + 420X  1mk
(ii) Q = McCc + M
(
)
(
)
=
1
1
= 640 – 16x + 67200 – 1980x = 67840 – 1696x
(iii) Heat gained = Heat lost  1mk
67200 + 420x = 67840 – 1696x
2116x = 640  1mk
x = 0.2930C  1mk
15. (a) The direction of velocity of the moon keeps on changing due to the changes in direction moon as it revolves around the
earth.
(b) (i) = 2  1mk = 2 x 3.142 x 6 = 37.704 rad/s  1mk
(ii) a = = r 
= 37.7042 x 0.6 = 852.955m/s2  1mk
(iii) T = Fc = mrw2  1mk
= 0.045 x 0.6 x (37.704)2 = 38.38N  1mk
(iv) v = wr = 0.6 x 37.704  1mk = 22.62m/s
(c) (i) Slope =

= 2000N/kg  1mk
(
)
1
1
1
 1mk
= 0.2 x 2000 = 400N  1mk
(iii) Centripetal force  1mk
(ii)
Page | 64
232/1,232/2,232/3 physics
KUWED EXAMINATION COUNCIL 2016
PHYSICS PAPER 232/2
PAPER 2
MARKING SCHEME
1.
- In a pinhole camera, the image is real while for a magnifying glass the image is virtual.
- In a pinhole camera, the image is inverted while for a magnifying glass the image is upright.
2.
3.
4.
5.
6.
Longitudinal waves
Transverse waves
Particles of the medium vibrate in a parallel direction to that Particles of the medium vibrate in a perpendicular direction
of the waves e.g. sound waves/seismic waves
to that of the wave e.g. water waves, light waves/radio waves
I=

Fuse not suitable 
Infra – red ´ mk ……………………… thermometer with blackened bulb ´ mk
– Polirisation 
/ potassium or dichromate to the acid.
- Local action 
– coating zinc plate with mercury 
1
R=
1
1
1


7.
= 1.45
r = 34.40
Cos 34.40 = 
d = 7.27cm2 
8. – Convex mirror – driving mirror 
/Security checks in supermarkets and vehicle parking yards
- Parabolic reflectors – flood lights and car reflector 
9. (i) Alpha ( ) particle/helium atom 
X = 88 
Y = 228 
10. An intrinsic semi conductor is doped with a trivalent. (valency 3 element) 
11. T = 30 – 10 = 20 X 10-3 sec 
1
1
f=

1
SECTION B
12. (a) (i) No effect on the galvanometer 
- No change in magnetic flux linkage.
(ii) The pointer deflects 
in the opposite direction – There is change in magnetic flux linkage.  1 mk
(b) The magnitude of induced e.m.f is directly proportional to the rate of change of magnetic flux.  1 mk
(c) (i) Input power = Ip x Vp 1 mk = 0.5 x 240  1 mk = 120W  1 mk
(ii) I =  1 mk =  1 mk = 3A
1
(iii) 36W
(iv) Efficiency =
x 100% =
 1 mk
= 30% 1 mk
1
13. (a)
+
+
+
+
+
+
2 – Direction  1 mk
Pattern at least 3 lines  1 mk
(i) 4 + 8 = 12F  1 mk
1
1
1
=
 1 mk
1
CT =
1
1
= 4F  1 mk
(ii) Q = CTV = 4 x 100 = 400C or = 4 x 10-4C.
(iii) p.d. across 6F capacitor, V1 =
 1 mk
= 66.67V  1 mk
p.d across 8F capacitor = (100 – 66.67)V  1 mk
= 33.33V
 1 mk
(c) Area of overlap  1 mk
Page | 65
232/1,232/2,232/3 physics
Distance between plates
Type of di-electric
material between the plates.
14. (a) U.V light dislodges electrons from zinc plate.  1 mk
Electrons are repelled by the negatively charged electroscope.  1 mk
This lowers the excess charge on the leaf leading to collapse.
- In figure 5 (b) U.V light dislodges electrons from zinc plate. Positively charged electroscope re- attracts electrons and
keep the charge constant.
(b) (i) Frequency of incident light  1 mk Work function of the surface  1 mk
(ii) h = slope of the graph
= (10 – 2.0) x 10-19/2.6 – 1.4 x 1015
= 6.67 x 10-3JS (Range 6.4 – 6.8) x 10-34JS
Extrapolation
Reading off f0 = 1.07 x 1015Hz
Work function = hf0 = 6.67 x 10-34 x 1.07 x 1015
= 7.4 x 10-19J
(
1
1
)
(c) hf =
= 2.29Ev
1
1
Since hf is less than , no photoelectric occur.
15. (a) (i) For all four diodes correctly drawn.
1
1
R 1
1
Output
(ii)
v
For atleast 1 full cycle.
 1 mk
(iii)
(iv)
t
v
v
t
t  1 mk
(b)
Time (days)
0
130
260
390
Amount decayed
0
0.5 x 1020
0.75 x 1020
0.875 x 1020
Amount remaining
1.0 x 1020
0.5 x 1020
0.25 x 1020
0.125 x 1020
Therefore 0.875 x 1020 would have decayed
or 8.75 x 1019  1 mk
Page | 66
232/1,232/2,232/3 physics
1.
KUWED EXAMINATION COUNCIL 2016
PHYSICS PAPER 232/3
PAPER 3
MARKING SCHEME
(b)
L (m)
0.1
0.3
0.5
p.d V
2.7
2.6
2.5
I (A)
0.38
0.22
0.16
7.11
11.82
15.63
R = ( )
-1
-1
I (A )
2.63
4.55
6.25
0.7
2.7
0.12
22.50
0.9
2.8
0.10
28.00
8.33
10.00
(d)
(e) Slope =
(f) (i)
1
1
= 0.312V-1
1
E=
1
1
= 3.205 voltsd
(ii)
1
rx
r x 0.312 = 1.4
1
r=
1
= 4.57
2.
Part A
(c)
Page | 67
232/1,232/2,232/3 physics
u (cm)
v (cm)
x=
y=
(
1)
(cm)
̅=
= 20.01
20.0cm 0.2
(f) C = 50cm  0.1
(g) K = 0.139kg
0.1217kg  K  0.152kg
(j)
Mass m (g)
Weight of m w (N)
L1 (cm)
L2 cm
y = (c – L2)p (kgcm)
x = L2 – WL1
30
60.0
2.50
35
46.7
1.33
40
40.0
1.00
20.00
20.04
20.00
(d)
10
0.1
65.6
33.4
2.27
26.84
20
0.2
63.2
35.9
1.93
23.26
30
0.3
61.0
38.0
1.64
19.70
40
0.4
59.0
40.0
1.37
16.40
50
0.5
57.0
42.0
1.10
13.50
60
0.6
55.2
43.8
0.85
10.68
(k)
= 0.08
Page | 68
232/1,232/2,232/3 physics
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
Kenya Certificate of Secondary Education
232/1
PHYSICS
PAPER 1
(THEORY)
TIME: 2 HOURS
SECTION A: (25 MARKS)
1.
Figure 1 below shows a burette that was initially filled to 12ml with a liquid of density 0.8g/cm³.
Figure 1
2.
3.
4.
5.
6.
7.
The liquid is allowed to run out for some time. If the volume of liquid removed from the burette has a mass of 14g,
determine the final reading on the burette.
(3mks)
If an umbrella is touched with a finger on inner surface when it is raining it allows the rain water to leak through. Give a
reason.
(1mk)
A vacuum pump was used to pump out air from the glass tube immersed in liquids as shown below.
After sometime the level of water rose to position X. Mark Y the corresponding position for the paraffin level. Give a reason
(2mks)
Explain the reason why a dropping dust particle in a still room does not trace a straight vertical path.
(1mk)
Figure 2 shows a flask filled with water. The flask is fitted with a cork through which a tube is inserted. When the flask is
cooled, the water level rises slightly, and then falls steadily.
Explain this observation.
(3mks)
Explain why copper is a better conductor of heat than iron.
(1mk)
Two candles A and B of equal lengths and thickness are joined together and balanced horizontally as shown below. Candle A
is lit.
State and explain what happens after a short time.
(2mks)
Page | 69
232/1,232/2,232/3 physics
8.
A uniform metre rule is supported by force of 3N and 2N as shown in figure 3 below.
9.
Determine the weight of the half metre rule.
(3mks)
When a mass of 2kg is hang from a single spring, the spring extends by a distance  = 5cm. Determine the total extension in
the set up below given that the springs are identical and weightless.
(2mks)
10. Trees planted along a busy road are observed to lean towards the road as they grow. Explain this observation. (2mks)
11. A particle starts from rest and accelerates uniformly in a straight line. After 3 seconds, it is at a distance of 9m from the
starting point. Determine the acceleration of the particle.
(3mks)
12. Bubbles of gas escaping from the bottom of a fish pond rises to the surface. It is observed that as bubbles rise, they get larger.
Explain this observation.
(2mks)
SECTION B: (55 MARKS)
13. (a) State Newton‘s second law of motion in terms of in momentum.
(1mk)
(b) A trolley of mass 5kg travelling to the right at 2m/s collides heads on with another trolley of mass 3kg travelling at 4m/s
to the left. Find their velocity after collision if the collision is perfectly inelastic.
(3mks)
(c) A bullet of mass 2g is fired with a velocity of 300m/s into a wooden block of mass 5kg suspended from a long string.
The bullet sticks into the wood and the two moves together.
(i) Find the velocity of the block and the bullet immediately after collision took place.
(3mks)
(ii) Calculate the height to which both swings upwards.
(3mks)
14. (a) State two factors that affect the efficiency of a pulley system.
(2mks)
(b) Figure 5 below shows a pulley system with the load rising at uniform speed.
From the information given, calculate:
(i) The velocity ratio of the machine.
(ii) Mechanical advantage of the machine.
(iii) Efficiency of the machine.
(1mk)
(2mks)
(3mks)
Page | 70
232/1,232/2,232/3 physics
(c) The handle of the screw-jack in figure 6 below is 42cm long and the pitch of the screw is 0.5cm.
(i) Calculate the V.R of the screw jack.
(2mks)
(ii) Calculate the effort needed to lift the load of 1188N.
(2mks)
15. (a) Explain why a drop of methylated spirit on the back of the hand feels colder than a drop of water at the same
temperature.
(2mks)
(b) A block of metal of mass 150g at 100C is dropped into a lagged calorimeter of heat capacity 40J/k containing 100g of
water at 25C. The temperature of the mixture is 34C. (s.h.c of water = 4200J/kgK).
Determine:
(i) Heat gained by the calorimeter.
(2mks)
(ii) Heat gained by water.
(2mks)
(iii) Heat lost by the metal block.
(2mks)
(iv) Specific heat capacity of the metal block.
(3mks)
(c) A student heated some water and noticed that it boiled at 102ºC. State one possible reason for this observation.
(1mk)
16. (a) Define angular velocity.
(1mk)
(b) A string of length 70cm is used to whirl a stone of mass 0.5kg in a circle of a vertical plane at 5 rev/s. Determine.
(i) The period.
(2mks)
(ii) The angular velocity.
(3mks)
(iii) The centripetal force.
(3mks)
(c) (i) Explain why bodies in a circular motion undergo acceleration even when their speed is constant.
(1mk)
(ii) The figure below shows a container with small holes at the bottom in which wet clothes have been put.
When the container is whirled in air at high speeds, it is observed that the clothes dry faster. Explain how the rotation of the
container causes the clothes to dry faster.
(2mks)
17. (a) The diagram below shows a uniform metre rule at equilibrium during a cold morning. State and explain the effect on the
equilibrium when the weather becomes hot during the same day.
(1mk)
(b) The diagram below shows a metallic metre rule at equilibrium. Study it and answer the questions that follow.
The spring had a constant of 25N/cm and stretched by 4mm at equilibrium. The 2kg mass was immersed halfway in the
water. Determine the following.
(i) Tension in the spring.
(2mks)
(ii) Upthrust.
(3mks)
(iii) Density of the 2kg mass. (Density of water = 1g/cm³).
(3mks)
Page | 71
232/1,232/2,232/3 physics
1.
2.
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
Kenya Certificate of Secondary Education
232/2
PHYSICS
PAPER 2
(THEORY)
TIME: 2 HOURS
State the property of light associated with formation of shadows.
Figure 1 below shows a negatively charged particle close to a positively charged plate.
Draw the electric field pattern.
Figure 2 below shows two identical bulbs connected in two circuits. The cells are of the same e.m.f.
(2mks)
3.
Compare the brightness of the bulbs in (a) and (b).
Figure 3 below shows a block of copper placed between two poles of a magnet.
(1mk)
4.
Sketch the magnetic field between the poles.
Figure 4 below shows an object placed infront of a concave mirror.
(2mks)
5.
6.
(1mk)
Use rays to locate the position of the image.
(3mks)
Figure 5 below shows a metre rule suspended by a thread such that it is in equilibrium balanced by a permanent magnet
attached to the metre rule and some weight.
Page | 72
232/1,232/2,232/3 physics
7.
8.
9.
If the soft iron is fixed to the bench, state and explain the effect on the metre when the switch is closed.
Figure 6 below shows a progressive wave incident from a shallow end to a deep end.
(2mks)
(a) Sketch the appearance of the wave in the deep region.
(1mk)
(b) State the property of waves demonstrated in the figure above.
(1mk)
A fathometer produces sound in a ship and receives two echo‘s where there is a raised sea bed. One after 2.5 seconds and the
other after 3.0 seconds. Find the height of the raised sea bank if the velocity of sound in water is 1460m/s.
(4mks)
Figure 6 below shows the path of light through a transparent material placed in air.
Calculate the refractive index of the transparent material.
(3mks)
10. State the name of the eye defect corrected by convex lens.
(1mk)
11. A heater of resistance R1 is rated P watts, V volts while another of resistance R2 is rated 2P watts, V/2 volts. Determine the
ratio R1 to R2.
(3mks)
12. State one use of microwaves.
(1mk)
13. Figure 7 below shows a diode D connected to a source of a.c current and a resistor.
Sketch in the axis below the output observed in the C.R.O.
E.m.f
Time(s
14. (a) State ohms law.
(1mk)
(b) Figure 8 below shows a large battery connected a resistor of 1000. The potential difference across the resistor is 50V.
5
Determine:
(3mks)
Page | 73
232/1,232/2,232/3 physics
(ii) The electrical energy dissipated by the resistor in one minute.
(c) Figure 9 below shows some resistors connected in part of a circuit.
(3mks)
Determine the effective resistance.
(3mks)
(d) Four 40w bulbs and six 100w bulbs were switched on for 2 hours in the morning and 3 hours at night each day for
domestic use in a certain institution. Find the monthly bill for the consumer given that the cost of electricity in the
country is at Sh.6.50 per unit. (Take one month to be of 30 days).
(3mks)
15. (a) State two factors that affect capacitance of parallel plate capacitor.
(2mks)
(b) Figure 10 below shows capacitors connected to 3v supply.
Calculate:
(i) The combined capacitance.
(ii) The charged stored in the 2.4F capacitor.
(iii) The charge stored in 2F capacitor.
16. (a) State lenzes law of electromagnetic induction.
(b) Figure 11 below show a magnet being pulled from a coil connected to a centre zero galvanometer.
(3mks)
(3mks)
(2mks)
(1mk)
(1mk)
(ii) Explain what would happen if the magnet was moved out faster.
(1mk)
(iii)\Explain the observation in b(i) above.
(2mks)
(c) (i) The turns ratio of primary to secondary coils in a 100% efficient transformer is 3: 1. Calculate the current through the
primary coil if the current in the secondary coil is 5A.
(3mks)
(ii) State how the energy losses are minimized in a transformer.
I Eddy current.
(1mk)
(1mk)
17. (a) Figure 12 below shows a cathode ray tube (C.R.O).
(b)
(c)
(d)
18. (a)
(i) Name the parts labelled A and B.
(2mks)
(ii) What are the functions A and C?
(2mks)
(iii) Explain how electrons are produced.
(2mks)
(iv) Give a reason why the tube is evacuated.
(1mk)
State what determines the quality of X-rays in an X-rays tube.
(1mk)
State one use of X-rays in industry.
(1mk)
An X-ray tube operates with a p.d. of 200kv. Only 0.5% of the kinetic energy of the electrons is converted into X-rays.
Calculate the frequency of the X-rays produced, take planks constant = 6.63 x 10 -34Js.
(3mks)
Figure 13 below shows a diagram of a Geiger Muller tube connected to a power supply and a pulse counter.
(i) Why should the argon gas be at low pressure?
(1mk)
Page | 74
232/1,232/2,232/3 physics
(ii) State the purpose of the bromine gas in the tube.
(iii) Suggest one way of increasing the sensitivity of the tube.
(iv) Find the value of a and b in the following equation.
(1mk)
(1mk)
(2mks)
234 U  a X  2
92
b
(b) In an experiment using a photocell, ultraviolet light of varying frequency strikes a metal surface. The maximum kinetic
energy (K.E max) of photoelectrons for each frequency, f, is measured. The graph below shows how the maximum
kinetic energy varies with the frequency, f.
(a) Use the graph to determine:(i) Planck‘s constant, h.
(ii) Work function of the metal.
(3mks)
(3mks)
Page | 75
232/1,232/2,232/3 physics
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK – 2016
232/3
PHYSICS
PAPER 3 (PRACTICAL)
CONFIDENTIAL
Question 1A
Each candidate requires the following items.
1. Watch glass
2. Plasticine
3. Marbles.
4. Stopwatch.
5. Vernier calipers.
6. Electronic balance (to be shared).
Question 1B
1. Rectangular glass block.
2. Optical pins.
3. Soft board.
4. Protractor
5. 30cm ruler.
6. Plain paper.
7. Plane mirror
Question 2A
1. 250ml beakers.
2. Bunsen burner.
3. Thermometers.
4. Tripod stand and wire gauze.
5. Stopwatch
6. Measuring cylinder (100ml) and water.
Questions 2B
1. A boiling tube
2. Some dry sand.
3. Water in a measuring cylinder labelled L.
4. Vernier calipers.
5. Half metre rule.
6. Tissue paper.
7. Weighing machine (to be shared).
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
Kenya Certificate of Secondary Education
232/3
PHYSICS
PAPER 3
(PRACTICAL)
TIME: 2½ HOURS
Question 1 (PART A)
You are provided with the following:
 A watch glass.
 A small piece of plasticine.
 A marble.
 A stopwatch.
 Vernier calipers.
 An electronic balance (to be shared).
(a) Measure the mass M of the marble.
M = …………………g
(½mk)
(b) Place the watch glass flat on the table with a small piece of plasticine to fix it firmly to the table at the place it touches.
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232/1,232/2,232/3 physics
(c) Release the marble from one end of the watch glass and time 10 complete oscillations with a stop watch. Repeat this three
times.
(d) Record your values in table 1 below
Table 1
Time for 10 oscillations
1
2
3
Periodic time T(s)
Find the average periodic time T.
T = …………………. s.
(e) Measure the diameter of the marble with the vernier callipers and hence find its radius.
Diameter d = …………………….. m
(f) Determine the volume (V) of the marble given that:
V 
4 3
r
3
(2mks)
(½mk)
(½mk)
(½mk
(1mk)
(g) Calculate the radius of curvature of the watch glass R from the formula.
Rr








(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
5gT 2
72 
2
(2mks)
Where g = 9.8m/s² and  = 3.142.
QUESTION 1 (PART B)
You are provided with the following apparatus:
A rectangular glass block.
Four optical pins.
A soft board.
A protractor.
30cm ruler.
2 white plain papers.
A plane mirror.
A vernier calipers (to be shared)
PROCEDURE
Trace the outline of the glass block on the white paper.
Draw a normal ON, 2cm from point X on side XY.
Measure an angle (i) 10º from the normal.
Place back the glass block on the outline and fix a plane mirror vertically along the length of the glass block on the opposite
side of XY using a cello tape as shown in the figure below.
Fix two pins P1 and P2 as shown in the figure.
By observing image of P1 and P2, locate two pins P3 and P4 such that they appear to be in line with images of P 1 and P2.
Remove the pins and the block. Join P 3P4 and produce the line to meet line P1P2 produced
Meause the perpendicular distance y.
Repeat the same for angles of 15º, 20º, 25º, 30º, 35º and 40º and record the results in table 2 below.
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232/1,232/2,232/3 physics
(NB: The paper work must be submitted together with the question paper).
Table 2
Angle i 10º
15º
20º
25º
30º
y(cm)
(j) Plot a graph of y(cm) against angle i.
(i) Use the graph to determine yo the value of y when i = 0º
yo = ……………… cm
(ii) Measure and record the breadth (b) of the glass block
b = ……………. Cm
(iii) Determine the value of  given that

b
yO
35º
40º
(4mks)
(5mks)
(1mk)
(1mk)
(2mks)
Question 2 (PART A)
You are provided with the following: A 250ml glass beaker.
 A Bunsen burner.
 A thermometer.
 A stopwatch.
 A Tripod stand and a wire qauze.
 A measuring cylinder 100ml.
 Water.
Set the apparatus as shown in figure below.
(a) Measure 100cm³ of water and pour it into the beaker. Take the initial temperature of the water.
To =……………… ºC.
(1mk)
Now heat the water to a temperature of 75ºC. Switch off the gas tap and place a thermometer into the beaker and start the
stopwatch when the temperature is 65ºC. Take the temperature TºC of water every two minutes. Record your results in the
table 3 below.
Table 3
Time, t(minutes)
2
4
6
8
10
12
14
Temperature, T(ºC)
(T – To) (ºC)
Log (T – To)
(5mks)
Plot a graph of Log (T – To) against Time (t).
From the graph find the value of Q given that Q = log (T – To) when t = 0.
Determine P, where P is the antilog of Q.
Calculate the temperature of the surrounding T S using expression
P = 65 - TS.
PART B
You are provided with the following:A boiling tube.
Some dry sand.
A liquid in a measuring cylinder labelled L.
Half metre rule.
A vernier calipers (to be shared).
A weighing machine (one per form).
Tissue paper.
A measuring cylinder.
(b)
(c)
(d)
(e)








(5mks)
(1mk)
(1mk)
(2mks)
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232/1,232/2,232/3 physics
Proceed as follows:
(f) Measure the length of the boiling tube.
h = ……………………. cm
(½mk)
(g) Put a little amount of sand in the boiling tube and place it in the measuring cylinder which is almost filled with liquid L. Add
sand, little by little until the tube floats upright as shown in figure below.
Measure the length, d, of the boiling tube which is above the liquid.
d = …………… cm
(h) Determine the length, t, of the boiling tube which is immersed in the liquid.
t = ………….. cm
(½mk)
(½mk)
(i) Remove the boiling tube from the measuring cylinder, wipe it dry (on the outside) and measure its mass, m, including the
sand inside.
m = ………….. g
(½mk)
(j) Measure the external diameter, D, of the boiling tube.
D = ………….. cm
(½mk)
(k) Determine the external radius, R.
R = …………… cm
(½mk)
(l) Using the formula m = 12R², determine  for the liquid.
(2mks)
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232/1,232/2,232/3 physics
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
232/1 – PHYSICS PAPER 1 MARKING SCHEME
1.
=
m
V
0.8 
2.
3.
4.
5.
6.
7.
V 
14 140

 17.5cm 3
0.8
8
14
V
Reading 12 + 17.5 = 29.5ml
(3mks)
Touching breaks surface tension of the water.
(1mk)
Paraffin less dense than water hence could occupy longer column to balance with pressure due to water column.
(2mks)
It is continuously knocked/bombarded/hit by the unseen air molecules/particles. (1mk)
Glass flask first contracts, decreasing in volume hence liquid rises. The liquid contracts at a faster rate than glass hence
reduction in its volume.
Copper has many free electrons for conductivity.
(1mk)
Tips to the right. Mass of A become less hence clockwise moments become greater than anticlockwise moment.
(2mks)
8.
F1d1 + F2d2 = F3D3
2 x 45 + 20w = 35 x 3
90 + 20w = 105
w = 0.75N
(3mks)
9. ext = 5 + 2.5 + 5 = 12.5cm
10. As vehicles move along the road, air moves at higher velocity resulting to corresponding decrease in pressure, thus
atmospheric pressure become greater pushing the trees towards a low pressure zone.
11. s = ut + 1/2at²
9 = 0 x t + 1/2a3²
9 = + 9/2a²
a² = 2
a = 1.41m/s²
(3mks)
12. Pressure acting on the gas bubble decreases as bubble rises. Volume increases (boyls law) pressure inside the bubble
increase as it rises.
(2mks)
13. (a) The rate of change of momentum is directly proportional to the external resultant force and takes place in the direction of
force.
(2mks)
(b)
m1v1 + m2v2 = (m1 + m21)v
8v = 5 x 2 – 3 x 4
8v = 10 – 12
V = -2/8 = -0.25/m/s
(3mks)
(c) (i)
m1 = 2g v = 300m/s
m2 5kg v = 0
(ii)
14. (a) - Weight of moving pulleys.
- Friction.
(2mks)
(b) (i)
V.R. = 4
(1mk)
24  10
 2.4
10  10
2.4
(iii)
E
 100  60%
4
2  227  42
 528
(c) V .R 
0.5
1188
1

 100  50
Effort 528
1
100
E  1188 

 4.5 N
528 50
(ii)
M .A 
(2mks)
(3mks)
(3mks)
15. (a) Methylated spirit evaporates faster than water hence it takes away heat from the body faster than water.
(b) Q = C
= 40 x (34 – 25) = 360J
(ii)
Q = MC
= 100 x 10ˉ³ x 4.2 x 10³ x (34 – 25)
(2mks)
(2mks)
Page | 80
232/1,232/2,232/3 physics
(iii)
(iv)
= 3780J
Heat lost = 360 + 3780
= 4140J
MC = 4140
C
(2mks)
(2mks)
4140
150  10  100  34 
3
C = 418.18Jkgˉ¹kˉ¹
(2mks)
16. (a) Angular velocity is the rate of change of angular displacement.
(b) (i)
(ii)
(iii)
T 
2
2

 0.20 sec
w
5  2
(1mk)
(2mks)
w = 5 x 2 = 10 rad/s
The centripetal force.
F 
mv 2

 mw 2  0.5  0.7  10  = 345.53N
2
(c) (i) Constant change in direction.
(ii) Heavy water particles move faster away through the holes.
(1mk)
(2mks)
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
232/2 – PHYSICS PAPER 2 MARKING SCHEME
1.
Light travel in a straight line. 
(1mk)
2.
 Arrows
 Lines
3.
The brightness is the same.
(2mks)
(1mk)
4.
(2mks)
5.
Arrows
 Rays
 Image
6.
Tips to the left South Pole attracts the North greater anticlockwise moment. (2mks)
7.
(1mk)
2d 1
8. 1460 
2.5
2d 2
1460 
3
d1 = 1825m d2 = 2190
Difference = 2190 – 1825
= 365m
Page | 81
232/1,232/2,232/3 physics
9.
n
1
 1.346
Sin 48
(3mks)
10. Long sightedness.
(1mk)
V2
P
11. R 1 
R2 
 12 2
2P
R1 : R2
1 : ⅛ or 8:1
12. - Communication.
- Cooking.

V2
8P
(3mks)
(any one)
(1mk)
13.
14. (a) Ohms law states that for a conductor the potential difference is directly proportional to current provided temp is constant
and all other physical constants remain same.
(1mk)
(b) (i)
V = IR
50 = 1000I
I 
50
 0.05 Amp.
1000
(3mks)
(ii) E = pt = IVt = 0.05 x 50 x 60
= 150 watts
(c)
R = 2 + 3 = 5Ω
1 1 45
9
 

5 4
20
20
20
R1 
9
20
RE  3 
9
2
32
9
2
5 
9
R 1 1 
(d)
(4 x 40) + (6 x 100) = 600 + 160
= 7602
In a day
760
 5  3.8kwh
1000
Cost in a month 3.8 x 30 x 6.50 = Sh.741
15. (a) - Distance between plates.
- Area overlapping.
- Material between the plates (dielectric)
(b) (i)
28
 2.4  F
28
Any two
(2mks)
(ii)
Q = CV
= 2.4 x 3 = 7.2C
(iii) Q = CV
= 3 x 1.6
Page | 82
232/1,232/2,232/3 physics
= 4.8C
16. (a) Lenz law states that the induced current flows in such a direction that produces magnetic effect that oppose the charge
producing it.
(1mk)
(b) (i) The pointer will deflect  showing current is induced and deflects back to zero. 
(ii) Pointer will be deflected further.
(iii) More current has being induced.
(c) (i)
I
NP
 S 
NS
IP
3
5

1 IP
IP = 1.67A
(ii) Laminating the core 
II Winding primary coils over secondary coils.

17. (a) (i) A – Control grid.
B – Anodes.
(ii) A – Control the brightness/No. of electron to screen.
C – Deflect the beam of electrons vertically.
(iii) Thermionic emission by heating the cathode directly or indirectly.
(iv) To reduce ionisation.
(b) The p.d across anode and cathode.
(c) Detect flaw and cracks in metal.
(d)
(2mks)
(2mks)
(1mk)
(1mk)
(1mk)
(1mk)
500
ev  hf
100
200000
0.5 
 1.6  10 19  6.63  10 34 f
100
f = 2.41 x 1017HZ
18. (a) (i)
(ii)
(iii)
(iv)
(v)
(b)
(1mk)
(1mk)
(3mks)
Argon – to initiate the discharge.
Quenching agent. (1)
Absorb energy of positive ions before they cause secondary electron emission.
Potential difference.
Potential difference.
a = 226
b = 88

6.0  0  1019
2.05  1.0  1015

6.0
 1034
1.05
= 5.71 x 10-34
Work friction
= hfo
= hfo
= 5.71 x 10-34 x 1.0 x 1015
= 5.71 x 10-19J
Page | 83
232/1,232/2,232/3 physics
CENTRAL KENYA NATIONAL SCHOOLS JOINT MOCK - 2016
232/3 – PHYSICS PAPER 3 (PRACTICAL) MARKING SCHEME
Question one
(a) Mass of marble (mark students value) ½
(d) Table 1
Award 2 marks for complete table values.
Correct to 2d.p. for time of oscillation and at least 2d.p. for periodic time.
Award 1 mark for complete table without adherence to accuracy.
Award 0 for incomplete table.
T = 0.70s (Use students averaged with a range of  0.02s ½
(e) d = 1.70cm  0.05cm ½
r = 0.85cm½
(f) V 
4
3
 3.142  0.85
3
= 2.573cm³¹
(g)
Rr
5gT 2
¹
2
72 
5  9.8  0.70
2

7  2  3.142
2
 0.85
= 0.9369cm ¹
* Check substitution and answer of the student.
PART B
(i) Table 2
Angle. iº
10 15 20 25 30
y(cm)
4.5 4.3 4.1 3.9 3.7
(Check trend)
4 marks – All correct.
3 marks – At least 5 correct.
2 marks – At least 3 correct.
1 mark – At least 2 correct
35
3.5
40
3.4
(j) Graph (5 marks)
(i) yo = 4.9cm ¹ (y – intercept of student)
(ii) b = 6.1cm  0.1 ¹
(iii)

b
6.1

¹
y O 4.9
= 1.245 ¹
Page | 84
232/1,232/2,232/3 physics
2.
(a) To = 23.0ºC ¹
Table 3
Time t (minutes)
Temperature T(ºC)
(T – To) (ºC)
Log (T – To)
2
61.0
38.0
1.580
4
57.0
34.0
1.531
6
53.0
30.0
1.477
8
51.0
28.0
1.447
10
49.0
26.0
1.415
12
47.0
24.0
1.380
14
4.50
22.0
1.342
(3 marks)
(1 mark)
(1 mark)
(b) Graph
(c) Q = y-intercept.
= 1.65 ¹
(d) P = antilog 1.65
= 44.67ºC ¹
(e) P = 65 – TS
TS = 65 – 44.67 ¹
= 20.33°C ¹
(f) h = 15cm  1cm ½
(g) d = 2cm  1cm ½ [Use students value]
(h) t = h – d
= 15 – 2
= 13cm ½ [Use students substitution of h and d]
(i) M = 61.2  10g ½ [Use students value]
(j) D = 2.53cm  0.1cm ½
(k) R 
2.53
 1.265cm ½
2
(l) M = 12R²

M
12 R 2
61 .2

¹ Correct substitution
12    1.265 2
= 1.014gcmˉ³ ¹
Page | 85
232/1,232/2,232/3 physics
KAMDARA JET - 2016
232/1
PHYSICS
SECTION A(25 MKS)
1. The figure below shows a burette partly filled with a liquid. The burette was initially full to the mark 0. If the quantity of the
liquid removed has a mass of 20g, determine the density of the liquid.
(2mks)
2. Water at 200C falls over a waterfall of height 40m. Calculate the temperature of water at the bottom of the waterfall if 80% of
potential energy at the top is converted into heat energy
(3marks)
3. A faulty thermometer reads 20C when dipped in ice a 00C and 950C when dipped in steam at 1000C. what would this
thermometer red if placed in water at room temperature of 180C?
(3 marks)
4. Xcm3 of substance A which has density 800 kg/m3 is mixed with 1000cm3 of water with a density of 1000kg/m3. The density
of the mixture is 960kg/m3. Determine the value of X
(3 marks)
5. The figure below shows a simple instrument designed by a student for weighing objects.
a) State what happens if one places an item on the weighing pan.
b) State two properties of water that make it suitable for this purpose.
6. The figure below shows an arrangement of demonstrate diffusion through solids.
(1 mark)
(2 marks)
The hydrogen gas is supplied for sometimes then stopped and the beaker removed. State and explain what is likely t be
observed when the hydrogen gas supply is stopped.
(3 marks)
7. A metal pin was observed to float in the surface of pure water. However, the pin sank when drops of soap solution were
carefully added to water. Explain this observation.
(1 mark)
8. Sauce pans have a plastic or wooden handles. It is observed that in the morning the pan feels colder than the wooden handle.
Explain the difference in this observation.
(2 marks)
9. A bullet moving at a velocity of 350m/s hits a tree trunk of diameter 70cm. It emerge from the opposite side with a velocity of
180m/s. Determine the average deceleration of the bullet in the trunk.
(3 marks)
10. The figure below shows a container with small holes at the bottom in which wet clothes have been put. When the container is
whirled in air at high speed, it is observed that the clothes dry faster.
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232/1,232/2,232/3 physics
Explain how the rotation of the container causes the clothes to dry why so fast.
(2 marks)
SECTION B (55 MARKS)
11. The table below shows the value of the resultant force F and time t for a bullet raveling inside the gun barrel after the trigger is
pulled.
Force F (N)
360
340
300
240
170
110
Times t (ms)
3
4
8
12
17
22
(a) On the grid provided plot a graph of force F against time t.
(5 marks)
(b) Determine from the graph:
(i) The time required for the bullet to travel the length of the barrel assuming that the force becomes zero just at the end of
the barrel.
(1 mark)
(ii) Impulse of the force.
(2 marks)
(c) Given that the bullet emerges from the muzzle of the gun with a velocity of 200m/s,
Calculate the mass of the bullet.
(3marks)
12. a) State the pressure law.
(1 mark)
b) The pressure (P) of a fixed mass of a gas at constant temperature T=300k is varied continuously. The corresponding
values of P and volume (v) of the gas are shown below.
Pressure (x105 Pa)
Volume (m3)
2.0
0.025
2.5
0.02
3.0
0.017
3.5
0.014
4.0
0.012
4.5
0.011
(i) Plot a graph of P against ⁄ using grid provided below.
(5 marks)
(ii) Given that P = 2RT , Find the constant R from the graph.
(2marks)
V
(c) A tin with an air tight lid contains air at a pressure of 1.0 x 10 5 Pa and a temperature of 120C. The air is heated in water
bath until the lid opens. If the temperature at which the lid opens is 880C,
Determine the pressure attained by the gas.
(3marks)
13. (a) State Archimedes Principle
(1 mark)
(b) The figure below shows a block of mass 50g and density 2000kg/m3 submerged in a certain liquid and suspended from
uniform horizontal beam by means of a string. A mass of 40g suspended from the other end of the beam puts the
system in equilibrium
(i) Determine the up-thrust force acting on the block.
(3 marks)
(ii) Calculate the density of the liquid.
(3 marks)
(iv) Calculate the new balance point of the 50g mass (the 40g mass remains fixed) if the liquid was replace with one
whose density was 1500kg/m3.
(3 marks)
14. a) A liquid at 80o in a cup was allowed to cool for 20 minutes. State two factors that determine the final temperature.
(2 marks)
b) What is meant by specific latent heat of evaporation?
(1 mark)
c) In an experiment to determine the specific latent heat of vaporization L of water, steam at 100oC was passed into water
contained in a well lagged copper calorimeter. The following
Mass of calorimeter = 80g
Initial mass of water = 70g
Initial temperature of water = 5oC
Final mass of calorimeter + water + condensed steam = 156g
Final temperature of mixture = 30oC
(Specific heat capacity of water = 4200JKg-1k-1 and specific heat capacity for copper =390J/kg/k)
Determine:
(i) Mass of condensed steam.
(2 marks)
(ii) Heat gained by the calorimeter and water.
(2 marks)
(iii) Given that L. is the specific latent host of vaporization of steam.
a) Write an expression for the heat given out by steam.
(1 mark)
Page | 87
232/1,232/2,232/3 physics
b) Determine the value of L.
(3marks)
15. (a) Distinguish between load and effort.
(2 marks)
(b) A mason uses a six wheel pulley system to raise a weight of 250N through a vertical height of 2.5m using the machine.
If the mason pulls using an effort of 500N. Calculate:
i) The velocity ratio of the pulley system.
(2 marks)
ii) The work done by the mason.
(3 marks)
iii) The useful work done by the pulley system.
(2 marks)
iv) The efficiency of the system
(3marks)
KAMDARA JET-2016
232/2
PHYSICS
TIME: 2 HOURS
SECTION A (25 Marks)
1. A ray of light makes an angle of 60° with a plane mirror as shown in Figure 1 below. The mirror is rotated through an angle
of 20° about the point O in a clockwise direction.
60°
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Figure 1
Determine the new angle of reflection.
(2mks)
Describe how you would charge a gold leaf electroscope by induction method
(2mks)
The figure 2 below shows a wire wound on a soft iron core.
Indicate the polarities of end A and B
(2mks)
Describe two defects in simple cells and ways in which they can be minimized.
(2mk)
Differentiate between Faradays law of electromagnetic induction and Lenz law.
(2mks)
Figure 3 below shows a moving coil microphone.
(2mks)
Diagram
An object is placed on the principal axis of a concave mirror. The image formed is upright and magnified. If the object
distance is 5cm and the image distance is 10 cm, determine the focal length of the mirror.
(2mks)
a) Differentiate between a transverse and a longitudinal wave.
(1mk)
b) Kenyatta National Hospital uses x-rays of wavelength 1×10-11m. Calculate the frequency of the x-rays. (Take c=
3×108m/s.)
(2mks)
A hunter standing some distance from a cliff blows a whistle and hears its echo 2 seconds later. How far is the cliff from the
hunter? (speed of sound in air=340m/s)
(2mks)
Calculate the speed of light in a medium of refractive index 4/3 given that the speed of light in air is 3×108m/s.
(2mks)
A wire of length 1.5m offers resistance of 6.5Ω to the flow of current through it. If the cross section area is 5.0×10 6 2
m .calculate the resistivity of the material.
(2mks)
The Figure 4 below shows two coils used to demonstrate mutual induction.
Diagram
State what happens to the galvanometer when K is closed.
(1mk)
Figure 5 below shows two parallel plate capacitors separated by a distance d units. Each plate has an area of A square units.
Diagram
Suggest one adjustment that can be made so as to increase the effective capacitance.
(1mk)
SECTION B (55 MKS)
(a) What is the purpose of a fuse?
(1 mark)
(b) The diagram in figure 9 below shows a ring – main circuit used by an electrician in a certain house.
(i) Identify two faults in the installation.
(2 marks)
ii) Explain why the 3 – pin plug fuse has a longer earth pin than the live and neutral pins.
(2 marks)
iii) Identify the type of transformer T used in the diagram in Fig. 9
(1 mark)
(c) A cooker rated 2.0kW was operated for 40minutes each for 30days. If the cost of each kilo – watt – hour unit is Shs.
15.50, Calculate the cost of electricity used.
(4 marks)
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232/1,232/2,232/3 physics
15. (a) The figure below show the displacement time graph of a wave traveling at 400cm/s.
Determine for the wave the:
(i) Amplitude
(1mk)
(ii) Period
(1mk)
(iii) Frequency
(2mks)
(iv) Wavelength
(3mks)
(b) The human ear can distinguish two sounds as separate only if they reach it at least 0.1s apart. How far from a wall
must an observer be in order to hear an echo when he shouts?(Speed of sound in air = 330ms-1)
(3mks)
16 The figure 7 below represents a cathode ray oscilloscope (C.R.O)
i) Name the parts labeled A and B
(2mks)
ii) What are the functions of parts labeled C and D
(2mks)
iii) Explain how electrons are produced.
(2mk)
iv) Give a reason why the tube is evacuated.
(1mk)
((b) i) Distinguish between cathode rays and light rays
(2mks)
(ii) State the function of A
(1mk)
(iii) An alternating p.d is applied across the Y-plates. State what is the effect on the position of the spot on the screen?
(1 mark)
(iv) A signal with a frequency of 50Hz is applied across the Y-plates. If the time base with a period of 0.04s is applied
across the X-plates, sketch a graph of p.d against time showing the number of waves that can be seen on the screen of
the C.R.O
(2 mks)
v) The tube of the CRO is coated with graphite. State three functions of the graphite coating
(3mks)
17. (a) State one similarity and one difference between a concave lens and a convex mirror
(2mks)
(b) A lens forms a focused image on a screen when the distance between the object and the lens is 100cm. the size of the
image is twice that of the object.
(i) What kind of lens was used? Give a reason
(2mks)
(ii) Determine the distance of the image from the lens
(2mks)
(iii) Determine the power of the lens
(3mks)
(c) The figure shown in figure 9 shown below is a human eye with a certain defect
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232/1,232/2,232/3 physics
(i) Name the defect
(1mk)
(ii) On the same diagram, sketch the appropriate lens to correct the defect and sketch rays to show the effect of the lens.
(2mks)
18 a) Name any two types of radiations given out in a radioactive process.
b) The half – life of cobalt – 60 is 5years.
How long will a sample take for the activity to decrease to 1/16 of its original value.
c) The graph below shows radioactive decay of iodine.
Use the graph to determine the:(i) Fraction of the amount remaining after 16.2 days.
(ii) Determine the half – life of iodine.
(iii) Mass remaining after 17 days.
(2mks)
(3mks)
(2mks)
(2mks)
(1mk)
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232/1,232/2,232/3 physics
KAMDARA JOINT - 2016
232/3
PHYSICS - PRACTICAL
TIME: 2 ½ HRS
1. You are provided with the followin
 a rectangular glass block
 4 optical pins
 a soft board
 a plain paper
Proceed as follows:
(a) Place the glass block on the plain paper with one of the largest face upper most. Trace round the glass block using a pencil as
shown below.
A
P1
P2
i
B
b
r
L
c
P3
P4
D
eye
(b) Remove the glass block and construct a normal at B. Construct an incident ray AB of angle of incidence, i = 20 0.
(c) Replace the glass block and trace the ray ABCD using the optical
(d) Remove the glass block and draw the path of the ray ABCD using a pencil. Measure length L and record it in the table
below.
Angle i0
L (cm)
L2 (cm2)
(
)
Sin2i
20
0.1170
30
0.2500
40
0.4132
50
0.5868
60
0.7500
70
0.8830
(6 marks)
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232/1,232/2,232/3 physics
(e) Repeat the procedure above for the angles of incidence given.
1
(f) Calculate the value of L2 and ; Record in the table.
1
(g) Plot a graph of (y-axis) against Sin2i.
Given that the equation of that graph is:
1
1
1
1
(5 marks)
(3 marks)
(i) Determine the – intercept C and the Sin2i – intercept B.
(j) Calculate the value of Q given by;
(2 marks)
(2 marks)
( )
(k) Hand in your constructions on the plain paper together with the answer script.
(2marks)
QUESTION 2
PART A
You are provided with the following:
- Two dry cells and a cell holder
- One voltmeter (0 – 5V)
- One ammeter (0 – 1A) or (0 – 2.5A)
- Six resistors labeled AB
- One resistor labeled R
- A switch
- 7 connecting wires
(a) Set up the circuit as shown in figure 2
(i) Close the switch, s. Read and record the voltmeter and ammeter readings
V = _______________________ volts
I = _________________________ Amperes
(ii) Determine the value of R given that R 
V
I
(1mks)
(1mk)
(b) Set the circuit as shown in figure 3
(i) With the crocodile clip across resistor 1 as shown in figure 3 above, close the switch, read and record the ammeter and
(ii) Repeat the procedure b (i) with crocodile clips across resistors 2, 3, 4, 5 and 6 respectively, each time recording the
corresponding values for V and I in table 2
Table 2
Number of resistors
1
2
3
4
5
6
p.d. (volts)
Current I (Amperes)
(4mks)
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232/1,232/2,232/3 physics
(c) On the grid provided plot the graph of p.d (V) (y axis) against I (A)
(d) Determine the slope of the graph at:
(i) p.d = 2.5V
(ii) p.d = 2.8V
(iii) What physical quantity is represented by the slope of your graph at any one point?
PART B
You are provided with the following;
 Half-metre rule
 Knife edge (raised)
 A thread (approx. 20cm in form of a loop)
 50g mass
(c) Determine the C.O.G of the half-metre rule.
(d) Diagram
(5mks)
(2mks)
(2mks)
(1mk)
(1 mark)
(iii) Pivot the rule at 15cm mark and balance it with the mass as shown. When it is well balanced, note and record the position of
the 50g mass;
(1 mark)
Position of 50g mass = _________________ cm mark
(iv) Use your results to determine the weight of the rule.
(2 marks)
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232/1,232/2,232/3 physics
KAMDARA JOINT - 2016
1.
2.
3.
4.
232/1
PHYSICS
2 HOURS
Marking scheme
Density = m/v
= 20/5
= 4 g/cm3
mgh = mc∆Ѳ
40 x 10 x 80% = 4200 x (x-20)
X =20.08 o C
0 -100 = 100 units
2-95 =93 units
1 unit =93/100 = 0.93 units
18 units = 18 x 0.93 =16.74 units
Mass of A
= 0.8kg
Mass of water = 1000g
Total volume =(1000+x)
Total mass = (1000+0.8)kg
Density mixture = 1000+0.8x
1000+x
0.96= 1000+0.8x
1000+x
960+0.96x = 1000+0.8x
(0.96-0.8)x = 1000-960
0.16x= 40
X=40
0.16
X=250cm3
3mks
5.
(a)The water level rises in the glass tube. 1mk
(b) -It is incompressible
-Pressure is transmitted equally in all directions 2mk
6. Water rises up the glass tube. 
Hydrogen diffuses out the porous pot faster than air diffusing into the pot creating partial vacuum (low pressure) hence
atmospheric pressure pushes water upwards.`
7. Soap lowers surface tension 1mk
8. Wood is a poor conductor of heat than pan. Compared, plastic would allow some loss of heat to the environment than wood.
Hence plastic feels colder than wood.
9. V2 = U2 + 2 as
1802 = 3502 + 2a x0.7
a= 1802 – 3502
2x0.7
= -64357.143m/s 2
10. The water is expelled through the holes when the container is rotated at high speed.
11. ( a) (i)A body continues in its state of ret or uniform motion in a straight line unless acted upon by an external force.1
ii) Ft = m (v-u)
(
)1
75 x 0.1 =
1
V = 30 m/s 1
(b) (i) M1V1 + M2V2 = (M1V2)v
V=

1
(
= 2.27 m/s
(ii) a =
(
)
)
= -1.136 m/s2
v2 = v2 + 2as
0 = (2.27)2 – (2 x 1.136s) 1
s = 2.268 m 1
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232/1,232/2,232/3 physics
12. Pressure of a fixed mass of a gas is directly proportional to the absolute temperature provided volume is kept constant.
1/v
40
50
59
71
83
91
(a) -Labeling axes
-3 correctly plotted points
From Y= 3x+c
Slope = 2Rt
Slope = Dy = 3.5-2
Dx 70-40
= 1.5x105
30
= 0.05x105
Therefore R= Slope = 0.05x105
600
R= 8.33
P1 = 1x 105 pa
T1 = 12+273)
T2 = 88+273
P2 = ?
P1 = P2
T1 T2
1x105= P2
285
361
P2= 1x105 x 361
285
= 126,666.7pa
13. (a) When a body is fully or partially immersed in a fluid, it experiences an upward force (Up-thrust) equal to the weight
of the fluid displaced.
(b) (i) When the body is in air, it weighs 0.5N 
When in the fluid, its weight =
20  0.4
 0.25N 
32
Up-thrust force = 0.50 – 0.25 = 0.25N 
(ii) The volume of the fluid displaced = volume of solid =
Up thrust = weight of fluid displaced
m
= 2.5 x 10-5m3 

=vxρxg
0.25
Density of fluid ρ =
  1 10 4  1000 kg / m 3
2.5
(iii)
The weight of fluid displaced = 2.5 x 10-5 x 1500 x 10 = 0.375N 
Hence the weight of the solid in the fluid = 0.5 – 0.375 = 0.125N 
The new balance point
0.4  20
 64cm 
0.125
14. - Surface area of cup/ sectional area of the cup
- Wind /air current/ drought present
- Temperature of surrounding area
-Density of the liquid (any two)
(b) The quantity of heat energy required to change unit mass of liquid to vapour without change in temperature.
(c) (i) Mass of condensed steam = 0.156-(0.08+0.07)
= 0.006kg
(ii) Q of heat procued by steam = 0.08x25x390
0.07x25x4200
780+7350
8130J
(ii)
(a) Qs= MLv+MCQ
(b) 8130= 0.006l+0.006x200x70
= 8130= 0.006l +84
= 8130-84 = 0.006Lv
8046 = 0.006Lv
1.341x 106 J/kg= Lv
15. a) Load is the force exerted by a machine while effort is the force applied to a machine
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232/1,232/2,232/3 physics
(b) Frictional force the machine is to overcome.
(c) (i) Velocity ratio V.R = 6
(ii) Distance moved by effort = 2.5 x 6= 15 M
Work done
=
Effort x effort distance
= 500x1.5 = 7500J
(iii) Useful work done = load x distance
= 25000x2.5 = 6250J
(iv) Efficiency = Useful work done
Total work done
= 6250x100
7500
= 83.33%
KAMDARA JET - 2016
232/2
PHYSICS
MARKING SCHEME
1.
2.
i2=r2=I + θ
=30°+20°=50°
-Touch the cap to discharge it
- bring a charged polythene rod close to the cap
- While the rod remain s in its position, touch the cap
- withdraw the finger and the rod at the same time.
2 marks
2 marks
3. A- South Pole
B- North Pole
2 marks
4.
Polarization-use a depolarizer (potassium dichromate/manganese (IV)) oxide
Local action-use pure zinc/amalgamation
2 marks
5.
Faraday‘s law- relates the magnitude of induced emf to the rate of change of
magnetic flux.
Lenz‘s law-relates the effect of the induced emf to the change producing it.
2 marks
Sound waves make the diaphragm to vibrate; vibration of the diaphragm
moves the coil to and fro.
- motion of the coil is perpendicular to the field hence induced emf of varying
magnitude sets up varying current in the coil
(2 marks)
Virtual image: f and V are both –ve.
(2 mark)
6
7
10cm
8
9
a) Transverse waves-displacement of particles is perpendicular to the
direction of wave motion.
Longitudinal- displacement of particles is parallel to the direction of wave
motion.
b) f=c/λ
=3×108÷1×10-11
=3×1019Hz
2d=V× t
2d=340×2
d= 340m
1mark)
(2marks)
(2marks)
Page | 96
232/1,232/2,232/3 physics
8
10
4/3= (3×10 )/V
V=2.25×108m/s
(2marks)
11
.
ρ=RA/L= (6.5×10-6×5.0)÷1.5
=2.17×10-5Ωm
(2 marks)
When K is closed the pointer deflects to the right then comes back to zero.
(1 mark)
Reduce the distance of separation (d) OR
Increase the area of overlap (A)
(1 mark)
a) Protective device in mains electricity that melts when current exceeds the
rating;
b)
i) Switch should be on live wire and not neutral;
Fuse should be on the live wire ;
(1mark)
ii)
To open the live and neutral earlier ;
Make contact earlier than live ;
(2mark)
12
13 14
iii)
15
(2mark)
Step down transformer
(1mk)
c)
2 Kw X 40/60 X 30= 40Kw-Hr
40 X 15.50
Sh 620
(4mark)
(a)
(1 mark)
(i) 3cm;
(ii) T = 0.4s;
(1 mark)
(iii)
1
T
1

;
0 .4
f  2.5Hz ;
f
(2 mark)
(iv) V = f;
4 =  x 2.5;
 = 4/2.5
 = 1.6cm
(b)
2s = V.t;
2s = 330 x 0.1;
2s = 33
s = 33/2
s = 16.5m;
(3 marks)
(3marks)
16
a)
i) A…Grid
B….Electron gun
ii) C……Vertical deflection
D….Horizontal deflection
(2marks)
iii) Beam of elecrons are boiled off from a cathode by thermionic emission
(2marks)
(2 marks
Page | 97
232/1,232/2,232/3 physics
and accelerated through thee cro tube by high voltages
iv) Tube is evacuated to eliminate collisions of cathode rays with air
molecules.
b) i) Cathode rays are negatively charged particles deflected by both
magnetic and electric field
Light waves not deflected by either magnetic or electric field
Ii) Accelarate the electrons and also focus them into a fine
(1mark)
(2marks)
(1 mark)
Iii) A straight vertical line on the screen
(1 mark)
(I mark)
(2marks)
17
(a)
Both form virtual images. in both images are diminished;
A diverging lens refracts light while the convex mirror reflects light. the diverging
lens
forms the image in front of the lens while the convex mirror forms an image behind
the
mirror;
(b)
(i)
Converging lens; It forms real images and it can form magnified
images;
(2 marks)
(2 marks)
(2 marks)
(ii)
v
v
u ;
u
3
v
u  v  100   v  100
3
v  75 cm;
1
(iii)
Power =
f
1 1 1
1 1
1 1 4
  

 ;

f u v
f 25 75 f 75
f  18.75cm  0.1875m;
3
1
p
 5.3D;
0.1875
(c)
(ii)
(i)
Long sightedness/ hypermetropia/presbyopia
(3 marks)
(1Mark)
(2 marks)
Page | 98
232/1,232/2,232/3 physics
18
a)
Alpha, beta, gamma(any two)
(2marks)
b)
11st 1 2nd 1 3 rd 1 4 th 1
2
4
8
16
4half  lifes  4  5  20 years
or
 
1  1 1
16
2
b) i)
7
5
(3 marks)
 20 yrs
16.2 days is ¼
(2 marks)
ii)
8.1 days ( should be shown on the graph
(2 marks)
iv)
70g
(1mark)
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232/1,232/2,232/3 physics
KAMDARA JET – 2016
232/3
PHYSICS PRACTICAL
MARKING SCHEME
Question 1
Angle i0
20
30
40
50
60
70
L2 (cm2)
L (cm)
6.2
6.4
6.6
7.0
7.3
7.7
S=∆Y/∆X=
C=0.0285
B=1.92
Q= -(
X
1
=
1
1
(
)
Sin2i
38.44
0.0260
0.1170
40.96
0.0244
0.2500
43.56
0.0230
0.4132
49.00
0.0204
0.5868
53.29
0.0188
0.7500
59.29
0.0169
0.8830
= -0.01 458
) = 1.0237
Page | 100
232/1,232/2,232/3 physics
QUESTION 2
(a) (i)
V = 2.2Volts 1mk
I = 0.24 Amperes 1mk
(ii)
R=
2.4
1mk
0.24
= 10 ± 1 1mk
(b)
Number of resistors
p.d (Volts)
Current I (A)
1
2.4
0.24
2
2.5
0.13
3
2.6
0.10
4
2.7
0.07
5
2.8
0.06
6
2.9
0.05
p.d:
 ½(mk) for each correct value to a maximum of 3mks
I:
 ½ mk for each correct value to a maximum of 3mks
(c) On the grid
- Axes: well labeled with units 1mk
- Scale: simple and uniform 1mk
- Plotting:  ½ mk for each correctly plotted point to a maximum of 2mks
- Curve; 1mk for curve though at least three correctly plotted points
(d) (i) Slope at p.d 2.5 =
2.65  2.5
1mk
0.05  0.14
0.15
=
 1.667 1mk
 0.09
(ii) Slope at p.d = 2.8V
3.1  2.8
0.025  0.06
1mk
0.3

0.035
 8.57

(iii) Resistance of the resistor s(1mk)
QUESTION 2 B
C.O.G 25 ± 0.5 cm
(i) position of 50 grams mass=4.7cm ± 0.1 marks
(ii) 0.05x11.3 = wx10
W = 0.565N
Page | 101
232/1,232/2,232/3 physics
1.
KASSU JET EXAMINATION - 2016
Kenya Certificate of Secondary Education
232/1
PHYSICS
PAPER 1
JUNE 2016
SECTION A (25 MARKS)
Attempt all the questions in this section.
The figure below shows a measuring cylinder with some water in it.
A metal cube of mass 18g is submerged in it. Given that the density of the metal is 4.167 g/cm3, indicate the new level of the
liquid.
(2 mks)
2.
3.
4.
5.
6.
7.
Explain how temperature affects surface tension.
(2 mks)
A drop of blue ink is introduced at the bottom of a beaker containing water. It is observed that after sometime, all the water in
the beaker turns blue. Name the process that takes place.
(1 mk)
The figure below shows a uniform metre rule pivoted at the 20cm mark. It is balanced by a weight of 3.5N suspended at the
5cm mark.
Determine the weight of the metre rule.
The diagram below shows a sketch graph of resultant force against velocity for a body falling through air.
(3 mks)
(a) Give the name given to the velocity of the body at point a.
(b) Explain why the resultant force is equal to zero for the velocity given in (a) above.
A student dipped a mercury thermometer into a very hot liquid.
(a) State what is observed.
(b) Explain observation in (a) above.
Three identical springs A, B and C are used to support 25.5N weights as shown below.
(1 mk)
(2 mks)
(1 mk)
(1 mk)
If the weight of the horizontal bar is 2.5N, determine the extension of each spring given that 6N causes an extension of 2 cm.
(3 mks)
Page | 102
232/1,232/2,232/3 physics
8.
The diagram below shows the effect of heat from the heater on two surfaces …………… surface.
(i) How does the heat from the heat reach the surface?
(1 mk)
(ii) State what is observed from the set up after a few minutes.
(1 mk)
9. Trees planted along or near the road seem to bend towards the road. State and explain the observation.
(2 mks)
10. Figure below shows a u-tube upon which a gas has been enclosed on one end with mercury in it. Calculate the pressure of the
gas.
11. State two sources of errors in an oil drop experiment.
(2 mks)
SECTION B (55 MARKS)
Attempt all the questions in this section.
12. (a) (i) Define the term angular velocity ( ).
(1 mk)
(ii) A body in a circular path is said to be accelerating and yet it moves in a constant speed. Explain.
(1 mk)
(b) A stone of mass 500g is attached to a string of length 50cm which can break when the tension exceeds 20N. The stone is
whirled by a student until the string breaks at a point 100 cm above the ground. (Take g, as 10 m/s 2).
(i) In what position does the string break.
(1 mk)
(ii) Calculate the angular velocity at which the string breaks.
(3 mks)
(iii) Time taken by the stone to reach the ground.
(3 mks)
(iv) Distance from the feet of the student to the point the stone strokes the ground.
(2 mks)
13. (a) A hydraulic lift is used to raise a load of 100 kg through a height of 2.0 m. the radius of
the effort piston is 1.6cm while the load piston has a radius of 8.0cm. If the machine is 75% efficient; calculate:
(i)
The velocity ratio.
(2 mks)
(ii)
(1 mk)
(iii)
Effort required
(1 mk)
(iv)
Energy wasted in using the machine
(2 mks)
(c) A block and tackle pulley system is used to lift a mass of 200 kg. If the machine has a velocity ratio of 5, and efficiency
of 80%;
(i) Sketch in the space provided below the possible arrangement of the system.
(2 mks)
(ii) Determine the effort required to lift the load.
(2 mks)
14. (a) State Newton‘s first law of motion.
(1 mk)
(b) A wooden block resting on a horizontal bench is given an initial velocity, U, so that it slides on the coach surface for a
distance, d, before coming to a stop. The values of, d, were measured and recorded for values of initial velocity. The
figure below shows a graph of U2 against d.
Page | 103
232/1,232/2,232/3 physics
(i) Determine the slope of the graph.
(3 mks)
(ii) Given that U2 = 20 kd, where K is a constant for the bench surface, determine the value of K from the graph.(3 mks)
(iii) State how the value of K would be affected by a change in the roughness of the bench surface.
(2 mks)
(c) A car of mass 800 kg starts from rest and accelerates at 1.2 ms -2. Determine its momentum after it has moved 400m from the
starting point.
(4 mks)
15. 300g of ice at 00c is dropped into a copper calorimeter containing warm water of mass 60g at 60 0c. it‘s observed that only
80% of ice melted.
(Take: Specific heat capacity of water = 4200 Jkg-1k-1
Heat capacity of copper
= 400 JK-1)
(a) Determine the final temperature of the mixture.
(1 mk)
(b) Determine the heat lost by calorimeter.
(2 mks)
(c) Determine the heat lost by warm water.
(2 mks)
(d) Determine the specific latent heat of fusion of ice.
(3 mks)
(e) It‘s observed that if the temperature if warm water used was 80 0c, then all the ice could have melted. What would be the
final temperature of the mixture? Use the value of specific latent heat of fusion obtained in (d) above.
(3 mks)
16. (a) A concrete block of value, V, is totally immersed in sea water of density, S. Write an expression for the upthrust on the
block.
(1 mk)
(b) A certain solid of volume 50 cm3 displaces 10 cm3 of kerosene (density 800 kg/m3). When floating. Determine the
density of the solid.
(4 mks)
(c) State the condition necessary for a body to float in a fluid.
(1 mk)
17. (a) A mercury thread 200 mm long traps a gas in a long glass tube. The length of the gas column is 100 cm when the tube if
held horizontally. The atmospheric pressure is 750 mmHg. Calculate the length of the gas column when the tube is held
vertically with the open end facing downwards.
(3 mks)
(b) State Boyle‘s law.
(1 mk)
(c) 250 cm3 of a gas is collected at a pressure of 900 mmHg and 27 0c temperature. Determine the volume of this gas if the
pressure is reduced to 500 mmHg and temperature 19 0c.
(2 mks)
K A S S U J. E .T.E XA M I N A T I ON 2016
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1.
232/2
PHYSICS
Paper 2
2 Hours
SECTION A: (25 MARKS)
In figure 1 two mirrors M1 and M2 are inclined at right angles to each other.
Diagram drawn to scale
Figure 1
Trace the reflection of the ray through the two mirrors and find the angle between the incident ray and reflected ray of mirror M2.
(2 marks)
2. When rod X was rubbed with material Y it was observed that the material acquired a negative charge.
a) State the charge on rod X after rubbing
(1 mark)
b) Explain how rod X acquired the charge stated in (a) above.
(1 mark)
3. An iron ring is placed between two magnets as shown in figure 2.
Iron ring
Figure 2.
(a)Sketch the magnetic field pattern between the poles and mark the neutral point, Xon the diagram .
(2 marks)
(b) State one application of the concept tested above.
(1mark).
4. A charge of 180 Coulombs flows through a lamp every minute. Calculate the number of electrons involved. (Take charge of
an electron e, =1.6x10-19C).
( 2 marks)
5. Table 1 shows radiations and their respective frequencies.
Yellow light
Gamma rays
Micro waves
Frequency (Hz)
1 x 1015
1 x 1022
1 x 106
1 x 1011
Table1
a) Arrange the radiation in order of increasing energy.
(1 mark)
b) State the reason why radio waves signals are easier to receive than TV signals in a place surrounded by hills.
(1 mark)
6. Figure 3shows a metal rod PQ connected to a d.c supply and placed between two magnets.
Figure 3
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7.
8.
a) Indicate on the diagram the direction of force on rod PQ and magnetic field pattern between the two magnetic poles only.
(2 marks)
b) State one way in which the direction of force can be made to change. (1mark)
An explosion in a quarry takes place at a distance of 70m from an observer. An echo from a cliff 50m beyond the source of
the explosion is heard by the observer 0.5 seconds after he sees the flash from explosion. Calculate the velocity of sound in
air.
(3 marks )
(a) Figure 4below shows the path of a ray of light through a triangular prism ABC of refractive index 1.50. is parallel to
AC.
Figure 4
Determine the angle of incidence on the side AC.
b) Figure 5 shows the image formed by convex mirror
9.
(3marks)
Sketch rays on the diagram to show the position of object
(2 marks)
In an experiment to study interference in sound waves two identical loudspeakers are connected to an audio frequency
generator so that they act as coherent sources L1 and L2 as shown in figure 6.
A
P
L1
L2
A1
O
Figure 6
An observer walking several metres ahead and a long a line to LI L2 identifies pointsAandA1as the first positions of loud
sound on either side after the loud sound at the middle position O between the two sources.
(2 marks)
(a) Explain the meaning of the term coherent source.
(1 mark)
(b) Name the type of interference occurring at the points O,A, and A1.
(1 mark)
10. Distinguish the n-type and p-type semiconductors.
(1 mark)
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SECTION B: 55 MARKS
11. a) Figure 7 shows a source of α,β and r-radiation placed infront of a set of barriers A,B
and C
Figure 7
A is a thick sheet of paper, B is a thin sheet of aluminium foil and C is a thin sheet of lead. Name the radiation detected in the
regions marked X, Y and Z.
(3 marks)
b) The figure 8 below shows the features of a diffusion cloud chamber used for detecting radiation.
Figure 8
i) Explain how radiation from the source is detected in the chamber.
(4marks)
ii) What type of radiation can the device detect?
(1mark)
c) The count rate recorded for a certain source is 256 counts per second. What count rate is recorded 20 days later, if the halflife of the source is 5 days.
(2marks)
12. (a) A house has five rooms each with 240V,60W bulbs.If the bulbs are switched on from 7:00pm to 10:30 pm;
(i) Calculate the power consumed in the month of April in Kilowatt-hours
(2marks)
(ii) Find the cost per month for lighting these rooms at Ksh6.70 per unit.
(2marks)
(b) A student designed a transformer to provide power to an electric bell marked 24W,6V from a mains supply 240V. He
wound coils, 50 turns and N turns on an iron ring core. When he connected the coil of 50 turns to the bell and N turns
coil to the a.c source, he found out that the transformer was only 80% efficient. Find;
(i) The value of N.
(2marks)
(ii) The current in the primary coil.
(2marks)
(c) The figure 9. shows a connection to the three- pin plug.
Figure 9
(i) Name the cables A, B and C and state their colours.
(ii) Why is the fuse connected to cable C.?
(iii) State one reason why in domestic wiring system appliances are connected in parallel.
(3marks)
(1mark)
(1 mark)
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13. Figure 10 Shows an electric circuit with four capacitors A,B,C and D8 µF ,3µF,6 µF and 15 µF respectively connected to
12V battery.
Figure 10
(a) Determine ;
(i) The effective capacitance.
(ii) The charge of capacitor D.
(iii) The total energy stored.
(b) Explain one factor that determine the capacitance of a parallel plate capacitor.
14. (a)Figure 11shows the features of a cathode ray tube.
(3 marks)
(2 marks)
(2 marks)
(1 mark)
Figure 11
(i) Explain how the electrons are produced in the tube.
(ii) What is the purpose of the anodes?
(iii) Why is the tube evacuated?
(b) Figure 12shows the voltage of an a.c. generator on the screen of a C.R.O.
(1 mark)
(2 marks)
(1 mark )
Figure 12
If the time base calibration is 20 milliseconds/cm and the y- gain is 5V/cm , calculate;
(i) The frequency of the generator.
(2 marks )
(ii) The peak voltage of the generator.
(2 marks )
1
(c) A potential difference of 40kV is applied across an x-ray tube. Given that the charge of an electron is
and the
mass of an electron is
1
and Planck‘s constant =
Js;
(i) What is the effect of increasing the potential difference across the x-ray tube?
(1 mark)
(ii) Calculate the velocity with which the electrons strike the target.
(3 marks)
15. A Form 4 student carried out on experiment to investigate photoelectric effect. From the results a graph of stopping potential
1
Vs (y-axis) against the inverse of the wavelength was plotted and was as shown below.
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The equation of the graph is
Where: c =
1
,speed of light in air
e=
, charge of an electron
h = is the Planck‘s constant.
(a) From the graph, determine;
(i) The slope s of the graph.
(2 marks)
(ii) The Planck‘s constant h.
(2 marks)
(iii) The threshold wavelength 
(2 marks)
(iv) The threshold frequency
(2 marks)
(v) The work function
in electron volts (e.v)
(2 marks)
(b) On the same graph, sketch a graph which would be obtained if the student used a metal with greater threshold frequency,
(2 marks)
KASSU JET 2016
232/3
PHYSICS PRACTICAL
CONFIDENTIAL
Provide the following apparatus to the candidates.
Question one
 Nichrome wire SWG 28 mounted on a mm scale
 2 new dry cell (size D)
 A cell holder
 A switch
 An ammeter (0 – 1 A)
 A voltmeter ( 0 – 5 V)
 Six connecting wires three with crocodile clips
 A micrometer screw gauge (to be shared)
Question 2A
 A metre rule
 Knife edge (at least 20cm high)
 One 50g mass and one 100g mass
 Some two pieces of threads (at least 30cm long)
 100cm3 of water in a 250cm3 beaker
 100cm3 of kerosene in a beaker labeled L
 Some tissue paper
Question 2B
 Rectangular glass block ( 9.6cm x 6,0cm x 2.3cm)
 Four optical pins
 A soft board
 A plain sheet of paper
 Some cellotape
 A complete mathematical set
1
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KASSU JET EXAMINATION JUNE 2016
Kenya Certificate of Secondary Education
232/3
PHYSICS
Paper 3
(PRACTICAL)
TIME: 2 ½ hours
Question one
You are provided with the following:
 2 new dry cells size D
 A cell holder
 A switch
 An ammeter
 A voltmeter
 6 connecting wires at least three with crocodile clips
 Nichrome wire mounted on the metre rule labeld X
 A micrometer screw gauge (to be shared)
Proceed as follows
a. Connect the circuit as shown in the figure below
Wire X
A
b.
c.
Measure the voltage, E of the dry cell before closing the switch
E=…………………… V
(1mark)
Adjust the length L of the wire 0.2m, close the switch S and read the value of current and record in the table below.
0.2
Length L(m)
0.3
0.4
0.5
0.6
0.7
Current , I(A)
1 1
(A )
I
d.
Repeat the procedure in (c) above for the value of lengths given in the table
1
e. Calculate the values of and record in the table above.
I
1
f. On the grid provided plot a graph of
(y axis) against L
I
g.
h.
Determine the gradient of a graph
(i) Measure the diameter dof the wire in three points used and find the average diameter.
d1=…………………………d2 =……………………d3……………… mm
Average d=…………………………m
(ii) Determine the cross section area, A of the wire
Form the equation
1 kl Q
=
+
I AE E
:
(1mk)
(5mks)
(3mks)
(1mk)
(1mk)
(2mks)
determine
i) The value of k
ii) The value Q


(3mks)
(2mks)
(2mks)
Question 2
Part A
You are provided with the following
A metre rule
Knife edge raising 20cm above bench
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232/1,232/2,232/3 physics





One 50g mass and one 100g mass
Some water in a beaker
Liquid L in a beaker
Tissue paper
Proceed as follows:
a) Balance the meter rule on the knife edge and record the reading at this point.
Balance point = ………………………………m
(1mk)
For the rest of this experiment the knife edge must be placed at this position.
b) Set up the apparatus as shown in figure below. Use the thread provided to hang the masses such that the positions of support
x
100g
c)
Knife
edge
10cm
d
50g
Water
The balance is attained by adjusting the position of the 100g mass. Note that the distance x and d are measured from the knife
edge and the 50 mass is fully submerged in the water. Record the values of x and d.
i) x1 = ………………………………………………….cm
(1mk)
d = …………………………………………………..cm
(1mk)
ii) Determine W1 (weight of the object in water)
(2mks)
iii) Determine the upthrust Uw in water of the 50g in water
(1mk)
Now balance the metre rule when the 50g mass is fully submerged in the liquid L.
x2 =…………………………………………cm
(1mk)
Apply the principle of moments to determine the weight W 2 of 50g mass in the liquid L and hence determine the upthrust U L
in the liquid.
W2
(2mks)
UL
(1mk)
d) Determine the relative density R.D of the liquid L, given that
R.D =





a)
UL
Uw
(1mk)
Part B
You are provided with the following
A rectangular glass block
Four optical pins
A piece of soft board
A plain sheet of paper
Cello tape
You are also required to have your complete mathematical set.
Proceed as follows:
Place the plain sheet of paper on the soft board and fix it using the cellotape provided. Place the glass block at the centre of
the sheet, and draw its outline. Remove the glass block. See the figure below
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Prism outline
P1
P2
2cm
θ
P3
P4
d
Draw a normal at a point 2cm from the end of the longer side of the block outline. This normal line will be used for the rest of
the experiment.
b) By viewing through the glass from the opposite side stick two other pins P 3 and P4 vertically such that they are in line with the
images of the first two pins. Draw a line through the marks made by P 3 and P4 to touch the outline.
Measure and record in the table below the perpendicular distance d between the extended line and the line, P3P4. See figure
above.
c) Record this value in the table below and repeat the process for other angles shown in the table.
NB: The sheet of paper with the drawing must be handed in together with this question paper. Ensure you write your name
and index on the sheet paper.
(3mks)
ϴ(deg)
25
35
40
45
55
60
65
d(cm)
d) (i) On the grid provided, plot a graph of d (y –axis) against ϴ
(ii) Using the graph, estimate the value of d when ϴ = 0o
(5mks)
(2mks)
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1.
2.
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE FORTY JOINT EXAMINATIONS – 2016
Kenya Certificate of Secondary Education
232/1
PHYSICS
PAPER 1
(THEORY)
JULY/AUGUST, 2016
TIME: 2 HOURS
SECTION A: (25 MARKS)
Answer all the questions in this section in the spaces provided.
Figure 1 shows a measuring cylinder, which contains water initially at level A. A solid of mass 0.32g is immersed in the
water, the level rises to B.
Figure 1
Determine the density of the solid. (Give your answer to 3 significant figures).
(2mks)
The figure 2 below shows part of micrometer screw gauge with 50 divisions on the thimble scale. Complete the diagram to
(1mk)
Figure 2
3.
In the set up shown below, it is observed that the level of the water initially rises before starting to drop when the flask is
dipped in ice cold water.
Glass
Water
Co
Coloured
Glass
4.
Explain this observation.
(2mks)
When a Bunsen burner is lit below wire gauze, it is noted that the flame initially burns below the gauze as shown in Figure
(i). After sometime, the flame burns below as well as above the gauze as shown in Figure (ii).
5.
Explain this observation.
(2mks)
The reading on a mercury barometer at a place in 690mm. The barometer contains some air which exerts a pressure of
15Nmˉ². What is the pressure at the place Nmˉ². (Density of mercury is 1.36 x 104kgmˉ³).
(3mks)
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6.
Figure below shows a graph of how the vertical height through which a machine raises a mass 30kg varies with time.
Determine the power output of the machine after 40 seconds.
Figure below shows a ball projected horizontally. Use the diagram to answer question 7 and 8.
(3mks)
grou
A player taps the ball and makes it spin in anticlockwise direction as it moves.
Show the new path followed by the ball.
(1mk)
Explain how the ball attains the new path above.
(2mks)
A constant force is applied to a body moving with a constant speed. State one observable change in the state of motion of the
body likely to occur?
(1mk)
10. The figure below is a uniform bar of length 2.0m pivoted near one end. The bar is balanced horizontal by a spring.
7.
8.
9.
Given that the tension on the spring is 1.2N, determine the weight of the bar.
(3mks)
11. The figure below shows a long tube filled with water. The open end is then covered with a cardboard and tube is inverted. It
is observed that the water in the tube does not spill out.
Explain the observation.
(1mk)
12. A steel ball of mass 0.05kg was placed on top of a spring on a level ground. The spring was then compressed through a
distance of 0.2m.
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If the spring constant is 15N/m. Calculate the maximum height reached when the spring is released.
(3mks)
13. The volume of inflated balloon is observed to reduce when the balloon is placed inside a refrigerator. Use the kinetic theory
of gases to explain this observation.
(1mk)
SECTION B: (55 MARKS)
14. (a) The figure below shows a displacement-time graph of the motion of a particle.
Describe the motion of the particle in the region.
(3mks)
(i) OA……………………………………………………………………….…
(ii) AB…………………………………………………………………………..
(iii) BC…………………………………………………………………………..
(b) A hot air balloon falling through the air attains terminal velocity after a short-time. State the reason why it attains terminal
velocity.
(1mk)
(c) State Newton‘s second law of motion.
(1mk)
(d) A ball of mass 0.2kg is thrown vertically upwards with velocity of 8msˉ¹. The air resistance is 0.5N. Determine:
(i) the resultant force on the ball as it moves up;
(Take acceleration due to gravity g = 10msˉ²).
(2mks)
(ii) The acceleration of the ball.
(3mks)
(iii) The maximum height reached by the ball.
(2mks)
15. (a) Draw a single pulley arrangement with a velocity ratio of 2.
(2mks)
(b) Figure shows a wheel and axle being used to raise a load W by applying an effort F. the radius of the large wheel is R
and of the small wheel r as shown.
(i) Shows that the velocity ratio (V.R) of this machine is given by R/r. (3mks)
(ii) Given that r = 5cm, R = 8cm, determine effort required to raise a load of 20N if the efficiency of the machine is 80%.
(4mks)
(iii) It is observed that the efficiency of the machines increases when it is used to lift large loads. Give a reason for this.
(1mk)
16. (a) (i) Define the term latent heat of fusion.
(1mk)
(ii) 9816J of heat energy is required to completely convert m kg of ice at 0ºC to steam. Determine the value of m.
(Take latent heat of fusion of ice = 2.34 x 105Jkgˉ¹; specific heat capacity of water = 4200Jkgˉ¹kˉ¹, latent heat of
vaporization of steam = 22.26 x 106Jkgˉ¹).
(4 marks)
(b) The cooling curve shown in figure below is for a pure substance.
(i) What is the melting point of the substance?
(ii) Explain what happens in the region.
I
CD……………………………………………………………………
II
AB…………………………………………………………………….
(1mk)
(3mks)
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III
BC…………………………………………………………………….
(c) A beaker containing ether was placed on some water on a wooden block. Air was then blown through the ether using a
pump as shown in figure below.
State and explain what observation is made after sometime.
(2mks)
17. (a) When the temperature of water reaches the boiling point, bubbles rise to the surface.
(i) State what is contained in the bubbles.
(1mk)
(ii) State the reason why bubbles rise to the surface only at the boiling point.
(1mk)
(b) Figure below shows a graph of vapour pressure against the temperature of water vapour at Kerugoya town where mercury
barometer indicates a height of 650mm.
(i) Determine the atmospheric pressure of the town in Nmˉ².
(Take g = 10m/s² and density of mercury = 13600kg/m³).
(3mks)
(ii) Use the graph to determine the boiling point of water in the town.
(1mk)
(c) The pressure of helium gas of volume 10cm³ decreases to one third of its original value at constant temperature.
Determine the final volume of the gas.
(3mks)
18. (a) One of the factors that affect the centripetal force is the mass of the body. State two other factors.
(2mks)
(b) A mass of 400g is rotated by a string at a constant speed V in a vertical circle of radius 100cm. The minimum tension in
the string is 7.2N which is experienced at point T.
T

(i) Determine the velocity V of the mass at point T.
(3mks)
(ii) Determine the maximum tension in the string.
(2mks)
(c) The anchor of a ship is made of steel and has a weight of 3200N in air. A ship floating in water is held by the anchor
submerged in water. (Density of steel is 8000kgmˉ³).
Calculate.
(i) The volume of the anchor.
(2mks)
(ii) The up thrust on the anchor.
(2mks)
(iii) The apparent weight of the anchor.
(2mks)
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1.
2.
3.
4.
5.
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE FORTY
JOINT EXAMINATION – 2016
Kenya Certificate of Secondary Education
232/2
PHYSICS
PAPER 2
(THEORY)
JULY/AUGUST, 2016
TIME: 2 HOURS
SECTION A: (25 MARKS)
Answer all the questions in this section in the spaces provided.
State one property of light that a pinhole camera illustrates.
(1 mark)
It is observed that when a rod A is brought near the cap of a negatively charged electroscope, the divergence of the leaf
decreases. State two deductions that can be made about rod A from this observation.
(2 marks)
State the purpose of manganese (IV) oxide in a dry cell.
(1 mark)
A soft iron ring is placed between two poles of a magnet as shown in the figure below.
(a) Show on the figure the magnetic field pattern between the poles.
(b) State one application of soft iron in magnetism.
An object O is placed in front of convex mirror as shown in the diagram below.
(a) Complete the diagram to locate the position of the image, 1.
(3 marks)
(2 marks)
(1 mark)
6.
(b) State one practical application of a convex mirror.
(1 mark)
The figure below shows a wire carrying current whose direction is out of the paper. The wire is placed in a magnetic field.
7.
8.
9.
(a) Indicate on the figure the direction of the force F, acting on the wire.
(b) State what would be observed on the wire if the direction of the current is reversed (i.e. into the paper).
Explain how doping a pure semi-conductor produces on n-type semi-conductor.
State one example of a transverse-progressive wave.
The following reaction is part of a radioactive series.
(1 mark)
(1 mark)
(3 marks)
(1 mark)
(1 mark)
(b) Determine the values of  and y.
(2 marks)
10. State:
(a) Two applications of microwaves.
(2 marks)
(b) one detector of infrared radiation.
(1 mark)
11. State one factor that affects the speed of sound in a solid.
(1 mark)
12. The figure shown below illustrates crests of circular water wave-fronts radiating from a point source O in a pond.
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State how the depth of the pond at A compares with that at B.
SECTION B: (55 MARKS)
13. (a) State the meaning of the term critical angle as applied in refraction of light.
(b) The figure shows a ray of light incident on a glass-air interface.
(1 mark)
(1 mark)
(i) Show on the diagram the critical angle, c.
(1 mark)
(ii) Given that the refractive index of the glass is ag, and that the critical angle c = 42º, determine the value of is ag.
(3 marks)
(c) The figure shows an experimental set up consisting of a mounted convex lens L, cardboard screen with cross-wires at the
centre, a plane mirror, a metre rule and a candle.
Describe how the set-up may be used to determine the focal length, f, of the lens.
14. (a) The figure below shows parts of a simple electric motor.
(4 marks)
(i) Name the parts labelled A and B.
(2 marks)
(ii) State the function of each of the parts named in part (i) above.
(2 marks)
(iii)
State the advantage of using radial (curved) poles of a magnet over plane (flat) poles.
(1 mark)
(iv) Explain the significance of copper coil as part of an electric motor.
(2 marks)
(b) The graph in the figure below shows the displacement of a pendulum bob from its rest position as it varies with time.
(i) Determine the amplitude of the oscillation.
(1 mark)
(ii) What is the time for one complete oscillation?
(1 mark)
(iii) On the same graph, draw a sketch graph which represents a pendulum swinging with half the amplitude and twice the
frequency.
(2 marks)
(c) Plane water wave fronts are incident onto reflector SR as shown in the figure below. Show on the diagram the nature
and direction of the reflected wave fronts.
(1 mark)
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15. (a) State the property of lead that makes it a suitable material for shielding an x-ray tube.
(1 mark)
(b) State how an increase in temperature of the filament in an x-ray tube affects the nature of x-rays produced. (1 mark)
(c) The figure below shows the vertical deflection system of a Cathode Ray Oscilloscope (C.R.O).
(i)
(ii)
(iii)
(iv)
(d)
State how cathode rays are produced in Cathode Ray Oscilloscope.
(1 mark)
Show on the diagram the path of the cathode rays when the switch S is closed.
(1 mark)
State what is observed on the screen if the d.c. supply is replaced with a high frequency a.c. supply.
(1 mark)
An electric filament bulb is rated 24V, 0.5A.
Calculate:
(i) The power of the bulb.
(2 marks)
(ii) The energy dissipated by the bulb in 80 minutes.
(2 marks)
16. (a) State Faraday‘s law of electromagnetic induction.
(1 mark)
(b) The figure below shows a 12V, 24W lamp operated by a step-down transformer that is connected to a 240V mains
supply.
(i) Explain what is meant by the term ‗laminated core’ and state its significance in a transformer.
(ii) Calculate the efficiency of the transformer if the current through the primary coil is 0.12A.
(c) The figure below shows a conductor AB placed in a magnetic field.
(2 marks)
(3 marks)
State the direction in which the wire must be moved for the induced current to flow in the direction shown.
(d) Explain the meaning of the term ‘Hysteresis loss’ as applied in transformers and state how it can be reduced.
17. (a) State two properties of electric field lines.
(b) The figure below shows part of a circuit containing three capacitors.
(1 mark)
(2 marks)
(2 marks)
(i) Calculate the effective capacitance between A and B.
(3 marks)
(ii) Given that the potential difference (p.d.) across AB is 10V, what is the total charge flowing through the circuit?
(1 mark)
(c) State how an increase in thickness affects electrical resistance of a conductor.
(1 mark)
18. (a) The figure below shows the inner parts of a three-pin plug.
C
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232/1,232/2,232/3 physics
(i) Identify the pins A and B.
(2 marks)
(ii) State the reason why the pin B is normally longer than the other two pins A and C.
(1 mark)
(b) In an experiment to find the relationship between frequency of radiation and kinetic energy of photoelectrons in a
photoelectric device, the following graph was obtained.
Use the graph to answer the following questions.
(i) Determine the threshold frequency.
(ii) Find the plank‘s constant h. (Take the charge of an electron to be 1.6 x 10-19C).
(iii)Calculate the work function of the metal in joules.
(1 mark)
(3 marks)
(2 marks)
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232/1,232/2,232/3 physics
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE FORTY JOINT EXAMINATION – 2016
232/3
PHYSICS
PAPER 3
(PRACTICAL)
JULY/AUGUST 2016
TIME: 2½ HOURS
CONFIDENTIAL
Question 1:
- A resistance wire PQ mounted on mm scale. (SWG 30, diameter = 0.32mm)
- Ammeter (0 – 1A).
- A voltmeter 0 – 3V or 0 – 5V.
- 2 new size D dry cells and a cell holder.
- A switch labelled K.
- Seven connecting wires at least two with crocodile clips.
- A convex lens of focal length 20cm and a lens holder.
- A metre rule.
- A white screen.
- A candle.
Question 2:
- A metre rule.
- A knife edge raised 20cm above the bench.
- One 50g mass and a 100g mass.
- Some thread (2) 20cm each.
- Some water in a beaker.
- Some liquid L in a beaker (paraffin).
- Tissue paper.
- A rectangular glass block.
- 4 optical pins.
- A plain sheet of paper.
- Cello tape.
- A piece of softboard.
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE FORTY JOINT EXAMINATION – 2016
Kenya Certificate of Secondary Education
232/3
PHYSICS
PAPER 3
(PRACTICAL)
JULY/AUGUST, 2016
TIME: 2½ HOURS
Question 1
PART A
You are provided with the following.
 A resistance wire PQ mounted on a mm scale.
 An ammeter.
 A voltmeter.
 A switch K.
 Two new dry cells and cell holder.
 Seven connecting wires at least two with crocodile clips.
Proceed as follows:
(a) Set up the circuit as shown in figure 1 below.
(b) Open the switch and record the voltmeter readings.
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232/1,232/2,232/3 physics
E = …………………… volts.
(c) (i) Starting with L = 70cm, read and record the readings of voltmeter and ammeter in table 1 provided.
Table 1
Length L(cm)
70
50
40
30
20
10
(1 mark)
Current I(A)
P.d, V (Volts)
(ii) Repeat step c(i) above for other values of L given in the table, 1 above.
(d) Plot a graph of p.d (y-axis) against I.
(e) Given that the graph is governed by the equation E = V + Ir, determine.
(i) the e.m.f of the two cells in series.
(ii) the internal resistance of the two cells.
PART B
You are provided with the following.
- A lens and lens holder.
- A candle.
- A screen.
- A metre rule.
Proceed as follows:
Set up the apparatus as shown in figure 2.
(5 marks)
(5 marks)
(2 marks)
(2 marks)
(f) Starting with U = 30cm, adjust the position of the screen to obtain a sharp image of the candle. Record the value of V in
Table 2.
(g) Repeat the procedure in (f) for U = 40cm. Complete the table.
U(cm)
V(cm)
V
m
U
30
40
(2 marks)
Table 2
(h) Given that the focal length of the lens satisfies the equation f 
V
determine the average value of focal length f.
1 m
(3 marks)
Question 2
PART A
You are provided with the following:
 A metre rule.
 A knife edge.
 One 50g mass and a 100g mass.
 Some water in a beaker.
 Liquid L in a beaker.
 Tissue paper.
Proceed as follows:
(a) Balance the metre rule on the knife edge and record the reading at this point.
Balance point ……………………….. cm
For the rest of this experiment the knife edge must be placed at this position.
(1 mark)
(b) Set up the apparatus as shown in the figure 1. Use the thread provided to hang the masses such that the positions of the
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232/1,232/2,232/3 physics
Figure 1
The balance is attained by adjusting the position of the 100g mass. Note that the distance X and D are measured from the
knife edge and the 50g mass is fully immersed in water. Record the values of X and D.
X = …………………………………….. cm
(1 mark)
D = …………………………………….. cm
(1 mark)
Apply the principle of moments to determine the weight W 1 of the 50g mass in water and hence determine the upthrust Uw in
water.
(2 marks)
W1 = ……………………………………………………………………………………
Uw = ………………………………………………………………………
(1 mark)
N
Remove the 50g mass from the water and dry it using tissue paper.
(c) (i) Now balance the metre rule when the 50g mass is fully immersed in the liquid L. Record the value of the distance .
 = ………………………………………..cm
(1 mark)
(ii) Apply the principle of moments to determine the weight W 2 of the 50g mass in the liquid L and hence determine the up
thrust UL in the liquid.
W2 = …………………………………………………………………
(1 mark)
UL = …………………………………………………………………
(1 mark)
(d) Determine the relative density R.D of the liquid L, given that:
(1 mark)
R.D 
UL
Uw
(e) Find the density of liquid  in kg/m³. (Given that density of water in 1000kg/m³).
PART B
You are provided with the following:
 A rectangular glass block.
 Four optical pins.
 A piece of soft board.
 A plain sheet of paper.
 Cello tape.
You are required to have your own Mathematical set.
Proceed as follows.
(f) Place the plain sheet of paper on the soft board and fix it using the cello tape provided.
Place the glass block at the centre of the sheet, draw its outline. Remove the glass block.
(1 mark)
(g) Draw a normal at a point 2cm from the end of one of the longer side of the block outline. This normal line will be used for
the rest of the experiment. Draw a line at an angle  = 25 from the normal. Stick two pins P 1 and P2 vertically on this line.
(h) By viewing through the glass from the opposite side, stick two other pins P3 and P4 vertically such that they are in line with
the images of the first two pins. Draw a line through the marks made by P3 and P4 to touch the outline. Extend the line
P1P2 through the outline (dotted line). Measure and record in the table the perpendicular distance d between the extended line
and the line P3P4 . Record this value in the table.
(i) Repeat the procedure in (g) and (h) for other values of  shown in the table.
25
35
40
45
55
60
56
 (deg)
d(cm)
(3 marks)
(i)Plot a graph of d against .
(ii)Use the graph to estimate the value of d when  = 0.
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE 40 JOINT EXAMS – 2016
232/1 – PHYSICS PAPER 1 MARKING SCHEME
1. Volume of water displaced
= 6.2 – 4.4
(j)
(5 marks)
(1 mark)
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232/1,232/2,232/3 physics
= 1.8cm³
= m/v

¹
6.32
1 .8
= 3.511gcmˉ³
= 3.51g/cm³ ¹
(2mks)
2.
(1mk)
3.
4.
5.
6.
When flask is dipped into ice cold water it contract first, reducing in volume ¹ hence water rises. Water then contacts more
than glass flask ¹ therefore the drop.
(2mks)
Initially the wire gauze conducts heat away so that the gas above does not reach the ignition ¹ temp/point. Finally the wire
gauze becomes hot raising the temperature of the gas above ignition point. ¹
(2mks)
P = Phg ¹
13600 x 0.690 x 10
= 93840
Atmospheric pressure = 93840 + 15 ¹
= 93860Nmˉ² ¹
(3mks)
P = force x velocity ¹
Power = Fd/t
30  10  20
¹
40
= 150w ¹
Or
Mg x h/t ¹ = 30 x 10 x 20/40 ¹
= 150w ¹
(3mks)
7.
Ball must rise upwards and land beyond the initial point. (1mk)
8.
The high velocity of the air above the ball creates a region of low pressue above ¹ it hence the higher atmospheric pressure
below it pushes it upward. ¹
(2mks)
Body accelerates if the force is in the same direction as the driving force or decelerates if in opposite direction. ¹ (1mk)
Anticlockwise moment = clockwise moment ¹
1.2 x 140 = 80w ¹
W = (1.2 x 140)/80
= 2.1N ¹
(3mks)
Atmospheric pressure acting on the cardboard is greater than pressure ¹ due to the column of water.
(1mk)
Elastic potential energy = mechanical potential energy.} ¹
Or
1
/2k² = mgh
1
/2 x 15 x 0.2² = 0.05 x 10h ¹
h = 0.6m
(3mks)
Lowering temperature causes a reduction of the speed of the air molecules/reduction in kinetic energy of air molecules, the
rate of collision of the molecules with the walls of the balloon decreases ¹ leading to decrease in pressure hence the volume.
(1mk)
9.
10.
11.
12.
13.
14. (a) OA – The particles moves at constant velocity/zero acceleration. ¹
AB – Particles are stationary/rest ¹
BC – Particles increasing velocity/accelerating uniformly. ¹
(3mks)
(b) Net force on balloon is zero or sum of upward = sum of down forces. (1mk)
(c) Newton second law motion state that the resultant force acting on a body is directly proportional to rate of change of
momentum and takes place in the direction of the force. ¹
(1mk)
(d) (i)
Mg + F ¹
2 + 0.5 = 2.5N ¹
(2mks)
(ii)
F = ma ¹
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232/1,232/2,232/3 physics
2.5 = 0.2a ¹
a = 12.5msˉ² ¹
NB: a must be negative since body is moving upwards.
(iii)
V² = u² + 2as
0 = 8² + 2(-12.5) ¹
S = 2.56m ¹
15.
(3mks)
(2mks)
Correct
Diagram ¹
Labelling ¹
(2mks)
(i) Distance travelled by the effort in one revolution 2R} ¹
Distance travelled by load = 2r
Velocity ratio (V.R) 
Effort dis tan ce 2R
R

¹ 
¹
2r
r
R
r
R 8cm
(ii) V .R 

 1.6 ¹
r 5cm
M .A
80
Efficiency 
 100 ¹ 
V .R
100
20 N
But M . A 

Effort
E
20 N
Therefore
 1.6  0.8 ¹
E
20 N
 2.6  0.8
E
20 N
Effort E 
1 . 6  0 .8
Therefore V .R 
= 15.6(3)N
= 15.6N ¹
(iii) When the load is large the effect of friction and weight of the moving parts is negligible. ¹
NB: Friction and weight of moving parts to be mentioned.
(1mk)
16. (a) (i) The amount of heat required to convert a given mass of substance from solid state to liquid state at its melting
point/without change in temperature. ¹
(1mk)
(ii)
Heat supplied = heat required to melt the ice + heat required to rise temperature of water to 100ºC. 
9816 = mlf + mC + mlv ¹
9816 = 2.34 x 105m + 4200 x 100m + 2.26 x 106m ¹
m
9816
2.914  10 6
= 0.003369kg ¹
(4mks)
Melting point = 58ºC ¹
CD – Solid cools ¹
AB – Liquid is cooling ¹
BC – Freezing is taking place/solidification. ¹
(3mks)
(c) Water on the bench cools/becomes ice. ¹ Blowing air into ether enhances evaporation, as evaporation occurs
ether cools getting latent heat of vapourisation from water. ¹
(1mk)
17. (a) (i)
Water vapour/steam. ¹
(1mk)
(ii)
Vapour pressure at boiling point exceeds prevailing external pressure. ¹
(1mk)
(b) (i)
P = gh ¹
(b) (i)
(ii)
Page | 125
232/1,232/2,232/3 physics
 13600  10 
650
¹
1000
= 88.4 x 10³N/m² or 88499N/m² ¹
(ii)
Reading of Bp at P = 88.4 x 10³ is 98  1ºC ¹
(c) P1V1 = P2V2
¹
P1 x 10 = V2P1/3 ¹
V2 = 30cm³
¹
18. (a)
Factors affecting centripetal are:
Angular velocity of the object. ¹
(b)
(i)
T = MV²/r – mg
MV²/r = T + mg
¹
0.4v²/1 = 7.2 + 0.4 x 10 ¹
V² = 28
V = 5.2919msˉ¹ ¹
(ii)
(3mks)
(1mk)
(3mks)
(2mks)
(3mks)
2
MV
 mg ¹
r
0.4  28  0.4

1.0
T 
= 15.2N ¹
(c)
(i)
V 

(2mks)
m
320
¹
8000
= 0.04m³ ¹
(ii)
(iii)
Upthrust = weight of water displaced
= Pvg
= 1000 x 0.04 x 10
= 400N ¹
Upthrust = weight in air – apparent weight.
400 = 3200 – apparent weight ¹
Apparent weight = 2800N ¹
(2mks)
¹
(2mks)
(2mks)
Page | 126
232/1,232/2,232/3 physics
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE 40 JOINT EXAMS – 2016
232/2 – PHYSICS PAPER 2 MARKING SCHEME
1. Rectilinear propagation of light. ¹
(1mk)
2. Either rod A is
(i) Positively charged. ¹
Or
(ii) Neutral. ¹
3. Oxidises the hydrogen gas to water.
Or Reduce polarization. ¹
4. (a)
Correct
- Pattern ¹
- Direction of the field –
North to South ¹
5.
(1mk)
(2mks)
(b) In electromagnets. In core of transformers. ¹
(a) Each ray correctly drawn (1mk)
Image shown a dotted (1mk)
(2mks)
(b) As driving or rear-view mirror in vehicles.
Or In supermarkets to guard against shoplifting. ¹ (Any)
6.
(2mks)
(1mk)
(1mk)
(a)
(1mk)
(b) Direction of motion (force) on the conductor is also reversed.Or The force is directed to the left hand side. ¹ (1mk)
7. Pure semi-conductor is doped with atoms of group 5 elements; ¹ an extra electron ¹ is donated from the bonding of each
impurity donor atom. These extra electrons improve ¹ electrical conduction of the semiconductor. (3mks)
8. Water waves. ¹
(1mk)
9. (a) Z: Beta  ¹
(1mk)
(b)  = 210 ¹
y = 84 ¹
(2mks)
10. (a) (i)
In cooking using microwave ovens. ¹
(ii)
In radar or telephone communications. ¹
(2mks)
(b) -Thermometer with a blackened bulb.
- Phototransistor.
- Heating effect it produces on the skin.
- A thermopile. ¹
Any one
(1mk)
11. Density of the solid.
Or Temperature of the solid. ¹
Any one
(1mk)
12. Point B is deeper than point A. ¹
(1mk)
Page | 127
232/1,232/2,232/3 physics
SECTION B:
13. (a) Angle of incidence in optically dense medium for which the angle of refraction in optically less dense medium is 90º.
¹
(1mk)
(b) (i)
Labeling ¹
(ii)
1
¹
Sin C
1

¹
Sin 42 o
 a g  1.4945 ¹
(1mk)
a g 
(3mks)
(c) Move the cardboard with crosswire along the metre rule until a sharp image of the cross-wires is formed alongside the
object cross-wires. ¹Measure the distance between the lens and the cardboard, ¹ this is equal to the focal length, f, of
the lens.Repeat the procedure ¹ and find the average value of f. ¹
(4mks)
14. (a) (i)
A: Split ring (commutator). ¹
B: Carbon brushes. ¹
(2mks)
(ii)
A (Split ring/commutator).
To reverse the direction of current in the coil after every half turn which allows continuous rotation of the coil.
¹
(1mk)
B (Carbon brushes).
To provide electrical connection to the coil. ¹
(1mk)
(iii)
Concentrates magnetic field towards the coil. ¹
(1mk)
(iv)
When current flows through it, it experiences a force, ¹ and motion ¹ is produced (rotation).
(2mks)
(b) (i)
Amplitude = 3cm ¹ from the graph.
(1mk)
(ii)
Time for 1 complete oscillation = 2.0 seconds ¹
(1mk)
(iii)
(c)
15. (a) High density. ¹
(1mk)
(b) Intensity (Quality) of x-rays produced increases. ¹
(1mk)
(c) (i) Current flows through the filament (cathode) heating it to high temperatures and electrons are set free/evaporate′
from the filament. ¹/Thermionic emission.
(1mk)
(ii)
Direction ¹
(1mk)
Page | 128
232/1,232/2,232/3 physics
A vertical line is observed along BAC. ¹
(1mk)
P = VI
= 24 x 0.5W ¹
= 12W ¹
(2mks)
(ii)
E = Pt = 12 x 80 x 60J ¹ = 57600J ¹
(2mks)
16. (a) The size (magnitude) of induced e.m.f is directly proportional to the rate of change of magnetic flux linkage. ¹
(1mk)
(b) (i) Laminated core-made of thin sheets of insulated soft iron plates. ¹ (1mk) Significance – Reduces size of eddy
currents. ¹
(1mk)
(ii)
Power input, VpIp = 240 x 0.12 ¹
= 28.8W
Power output

 100 %
Power input
OR
24W
¹

 100%
(iii)
(d) (i)
28.8W
(c)
(d)
17. (a)
(b)
= 83.33% ¹
Motion of conductor: Downwards. ¹
(1mk)
Energy loss inform of heat due to repeated magnetization and demagnetization of the core every time current reverses.
Reduced by: Use of soft iron core (which is easily magnetised and demagnetised. ¹
(1mk)
(i)
They never cross each other.
(ii)
They are close to each other where the field is strong and far apart where it is weak.
(iii)
They are directed towards the direction in which a free positive charge would move if placed at the particular
point in the field.
(iv)
Start at 90º from the positive charge and end on the negative charge at 90º.
Any 2
(2mks)
(i)
Parallel; Co = C1 + C2 = (4 + 2)µF = 6µF ¹
Series
1
1
1


CT
C1 C T
1 1
 
3 6
1
3 ¹

CT
6
6
C T   2F ¹
3
Q = CV = 2 x 10µC
= 20µC
¹
(c) Electrical resistance decreases ¹ when thickness of a conductor increases.
(3mks)
(ii)
18. (a) (i)
(ii)
(b) (i)
(ii)
(1mk)
(1mk)
A: Neutral pin. ¹
B: Earth pin. ¹
(2mks)
So as to open the socket shutters for pins A and C and earth the appliance before it becomes live. ¹
(1mk)
fo = 2.6 x 1014Hz (from the graph). ¹
(1mk)
wO
h
V S  f O
e
E
 Slope of the graph 
Slope 
h
e
1.24  0
¹
6.0  2.6  10 14
= 0.3647 x 10-14

h
= 0.3647 x 10-14 ¹
e
h = 0.3647 x 10-14 x 1.6 x 10-19Js
h = 5.8352 x 10-34Js ¹
(3mks)
W O = intercept along stopping potential axis
e
= 0.96V
 Wo = 0.96eV ¹
= 0.96 x 1.6 x 10-19J
Wo = 1.536 x 10-19J ¹
(2mks)
KIRINYAGA CENTRAL SUB-COUNTY EFFECTIVE 40 JOINT EXAMS – 2016
(iii)
Page | 129
232/1,232/2,232/3 physics
232/3 – PHYSICS PAPER 3 MARKING SCHEME
Question 1 PART A
1 (b) E = 3.0  0.1 volts ¹
1 (c) (i)
Table 1
Length (cm) 70
50
40
30
20
10
Current I(A) 0.28 0.34 0.38 0.50 0.60 0.82  0.02
P.d. V(V)
2.6
2.5
2.4
2.3
2.1
1.9
 0.1
Every row – Each correct value ½ marks – max 5 - 2½ marks
Total 5 marks
(d) On graph paper.
Axis – Quantity with units – 1 mark
Scale – Simple and uniform – 1 mark
Plotting – At least four correctly plotted - ½ x 4 = 2 marks
Extrapolation 1 mark
Correct value 1 mark
(e) (i) V = - rI + E
E = Y intercept = 3.0  0.1 
(ii)  r  Slope 
(1 mark)
V
1mark
I
OR
2.4  2.0 1 mark 0.4


0 .4  0 .7
 0.3
 = 1.33 1 mark
PART B: TABLE 2
U(cm) V(cm)
(g)
30
40
60
40
m
2
1
V
U
1 mark
1 mark
(h) f  60  20 cm 
1
1 2
f
2

40
 20 cm 
11
2 marks
20  20
 20cm 1 mark
2
Question 2 PART A
f 
Page | 130
232/1,232/2,232/3 physics
(a) Balance point = 49.5cm allowance of 0.5cm on the higher side. 1 mark
(b)  - 17.8cm 1 mark
D – 40.5cm 1 mark
W1 
1  17.8
 = 0.4395 2 marks
40.5
Uw = 0.5 – 0.4395 = 0.0605N 1 mark
(c) (i)  = 18.4cm 
(ii) W 2 
1  18.4
 0.4543N 1 mark
40.5
UL = 0.5 – 0.4543 1 mark
= 0.0457N
(d) R.D = 0.755 
(e) Density = 0.755 x 1000
= 755kg/m³ 
PART B (i)
55 60 65
(deg) 25 35 40 45
d(cm) 1.2 1.8 2.1 2.15 3.1 3.6 4.2
Each value ½ mark – maximum 3 marks
j(i)
Axis – Labelled with units 1 mark
Scale – Simple and uniform 1 mark
Plotting – 4 points - ½ mark each maximum 2 marks
Line through the origin 1 mark
j(ii) d = 0cm.
Page | 131
232/1,232/2,232/3 physics
1.
2.
3.
4.
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
Kenya Certificate of Secondary Education
232/1
PHYSICS
PAPER 1
(THEORY)
TIME: 2 HOURS
SECTION A: (25 MARKS)
Answer all the questions in this section in the spaces provided.
cm of substance A of density 800kg/m³ is mixed with 1000cm³ of water of density 1000kg/m³. The density of the mixture is
then 0.96/cm³. Determine the value of 
(3mks)
When washing clothes, it is easier to remove the dirt using some warm water containing soap than cold water. Explain this
observation.
(1mk)
Explain why a thick glass is more likely to break when hot water is poured on it than thin glass.
(2mks)
The figure below shows two identical burning splints. Placed on wood and metal blocks respectively it was observed that
when the flame reached the edge of the metal block the splint was extinguished while the other on the wooden block
continued to burn. Explain this observation.
(1mk)
5.
The figure below shows water level in limb Q of a glass tube. Indicate the corresponding water levels in limb N, O and P.
(2mks)
6.
A spring has a spring constant 4N/m. Two identical springs are connected end to end. Find their effective spring constant.
(2mks)
The figure below shows a solid sphere with its centre of gravity marked with a dot. The sphere is rolled on a horizontal
ground and comes to rest after. Some time.
7.
c.o.g
8.
9.
On the space provided below sketch the sphere and mark with a dot the most likely position of the c.o.g after it comes to rest.
(1mk)
Seen through a hand lens pollen grains particles in water move about randomly. Explain this observation.
(1mk)
A cork enclosing steam in a boiler is held down by the system shown below.
If the area of the cork is 20cm², and the force F is 300N, determine the pressure of the steam in the boiler.
(3mks)
10. The figure below shows light balls resting on a flat surface. A filter funnel is then inverted over them. State what is observed
when air is blown through the funnel.
(1mk)
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232/1,232/2,232/3 physics
11. Using the kinetic theory for gases, explain how a rise in temperature of a gas causes a rise in the pressure of the gas if the
volume is kept constant.
(2mks)
12. An aircraft 320m from the ground travelling horizontally at 50m/s releases a bomb. Calculate the horizontal distance covered
by the bomb from the point of release (ignore air resistance and g = 10m/s²).
(2mks)
13. The figure below shows two forces F1 and F2 acting on an object.
Show on the same figure the resultant force.
(1mk)
14. The uniform bar in the figure is pivoted at its midpoint it is in equilibrium under the action of two identical balloons with
equal volumes of different light gases at the same temperature.
Explain why the bar may not remain in equilibrium if the temperature of the surrounding changes.
(2mks)
15. In a vacuum flask, the double glass walls that enclose the vacuum are shiny. State the reason.
(1mk)
SECTION B: (55 MARKS)
16. (a) State two conditions necessary for a body to float in water.
(2mks)
(b) The figure below represents a block of uniform cross-sectional area 6.0cm² floating on two liquids A and B. The length
of the block in each liquid is shown.
Given that the density of liquid A is 800kg/m³ and that of liquid B is 1000kg/m³
determine.
(i) Weight of liquid A displaced.
(ii) Weight of liquid B displaced.
(iii) Density of the block.
17. (a) A certain powder of mass 100g was heated in a container by an electric heater rated 100w for some time.
below shows the variation of the temperature of the powder with time.
(3mks)
(3mks)
(4mks)
The graph
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232/1,232/2,232/3 physics
Use the graph to:
(i) Determine the melting point of the powder ………………………
(1mk)
(ii) Determine the quantity of heat supplied by the heater from the time the powder starts to melt to the time it has melted.
(iii) Determine the specific latent heat of fusion of the powder assuming the container absorbs negligible amount of heat.
(b) State one application of cooling caused by evaporation.
(1mk)
(c) Water of mass 2kg at 100°C is allowed to cool for 20 minutes. State two factors that determine the final temperature.
18. (a) Give a reason why the inside of a helmet is lined with sponge.
(1mk)
(b) The figure below shows a balloon filled with air.
When the mouth is suddenly opened, the balloon moves in the direction shown above by the arrow. Explain that observation.
(2mks)
(c) A rock of mass 150kg moving at 10m/s collides with a stationary rock of mass100kg. They fuse after collision.
Determine the
(i)
Total momentum before collision.
(2mks)
(ii)
Total momentum after collision.
(1mk)
(iii)
Their common velocity after collision.
(2mks)
(d) The figure below shows an object of mass 1kg whirled in a vertical circle of radius 0.5m at a uniform speed of 5m/s.
r = 0.5m
(i) Determine:
I the centripetal force on the object.
(3mks)
II the tension in the string when the object is at A.
(2mks)
III the tension in the string when the object is at B.
(2mks)
(ii) The speed of rotation is gradually increased until the string snaps. At what point is the string likely to snap. Explain.
(2mks)
19. (a) Using the pulley system shown a mass of 10kg is raised 2M by effort of 80N.
(i) Calculate the distance the effort moves.
(2mks)
(ii) How much potential energy does the load gain.
(1mk)
(iii) How much work is done by the effort?
(1mk)
(iv) What is the efficiency of these pulleys?
(2mks)
(b) A small pump develops an average power of 100w it raises water from a borehole to a point 10M above the water level.
Calculate the mass of water delivered in 30 minutes.
(3mks)
20. The figure below shows a set-up used to investigate Charles Law.
(i) State one missing item in the set-up.
(ii) Name two measurements to be taken in this experiment.
(iii) Explain how the measurements stated above may be used to investigate Charles Law.
(1mk)
(2mks)
(4mks)
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232/1,232/2,232/3 physics
1.
2.
3.
4.
5.
6.
7.
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
Kenya Certificate of Secondary Education
232/2
PHYSICS
PAPER 2
(THEORY)
TIME: 2 HOURS
SECTION A: (25 MARKS)
Answer all the questions in this section in the spaces provided.
Figure 1 shows a circuit contains a battery of cells V, a 3A fuse, F, a switch S, and two identical lamps L1 and L2. A current
of 2A flows through lamp L2 when the switch is open.
Figure 1
Explain why the fuse may blow when the switch is closed.
(2mks)
What property of light is suggested by the formation of shadows?
(1mk)
A student holds a large concave mirror of focal length 1M, 80cm from her face.
State two characteristics of her image in
the mirror.
(2mks)
A positively charged rod is brought close to the cap of a gold leaf electroscope, it is observed that the gold leaf diverged
further. Explain this observation.
(2mks)
The chart below shows an arrangement of different parts of the electromagnetic spectrum.
Infrared rays
B
Ultra-violet
Gamma-Rays
-Rays
Name the radiation represented by B.
(1mk)
In a cathode ray oscilloscope the time base is set at 25ms/mm. Given that crest to crest of a signal covers a length of 6cm,
determine the frequency of the signal. (3mks)
Two magnets A and B in figure 2 were brought from a point high above a table towards a steel pin.
State with a reason which magnet will attract the pin at a bigger height above the table.
(2mks)
A radioactive sample of half-life 260 days initially has 2.0 x 1020 radioactive atoms. Calculate the number of atoms that
would decay after 780 days.
(3mks)
9. Explain how a P-type semiconductor is made from a pure semiconductor.
(2mks)
10. Distinguish between transverse and longitudinal waves.
(2mks)
11. A policeman standing between two high walls fires a gun. He hears the first echo after 3 seconds and the next 2 seconds
later. What is the distance between the wall. (Take velocity of sound = 330m/s).
(2mks)
12. Figure 3 shows two parallel current carrying conductors Y and Z placed close to each other. The direction of the current is
into the place of the paper.
8.
Figure 3
X
(i) Sketch the magnetic field patterns.
(ii) Indicate the force F due to the current.
Y
(1mk)
(1mk)
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232/1,232/2,232/3 physics
SECTION B: (55 MARKS)
13. The figure 4 shows a circuit with a coil used to warm oil in a beaker.
Figure 4
(a) State the Ohm‘s Law.
(b) (i) Explain how heat is produced in the coil.
(ii) Given that the reading of the ammeter is 2.5A, determine the resistance of the coil.
(iii) How much heat is produced in the coil in a minute?
(iv) Give two changes that can be made in the set-up in order to produce more heat per minute.
(c) Figure 5 below shows a circuit used to study behaviour of diode.
(1mk)
(2mks)
(3mks)
(3mks)
(2mks)
Figure 5
State the behaviour of voltmeter reading as Jockey J is moved from S to R. Explain.
14. (a) State two properties of -rays.
(b) Figure 6 below shows an -ray tube. Use it to answer questions that follow.
(2mks)
(2mks)
Figure 6
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(c)
Name parts labelled A and B.
(2mks)
Explain how a change in the potential across P changes the intensity of the -rays produced in the tube.
(2mks)
During the operation of the tube, the target becomes very hot. Explain how this heat is caused.
(2mks)
Name a suitable material for the target.
(1mk)
Name the part labelled T.
(1mk)
Why is the tube evacuated?
(1mk)
In a certain -ray tube, the electrons are accelerated by a p.d. of 24000V. Assuming all the energy goes to produce rays, determine the frequency of the -rays produced. (Plank‘s constant h = 6.62 x 10¯34Js and charge on an electron, e
= 1.6 x 10¯19C).
(3mks)
15. Figure 7 below shows a narrow beam of white light onto a glass prism.
Figure 8
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232/1,232/2,232/3 physics
(i) What is the name of the phenomenon represented in the diagram?
(1mk)
(ii) Name the colour at X and Y. Give a reason.
(3mks)
(iii) What is the purpose of the slit?
(1mk)
(b) Figure 8 below shows the path of ray of yellow light through a glass prism.The speed of yellow light in the prism is 1.8 x
108m/s.

r
Figure 8
(i) Determine the refractive index of the prism material (speed of light in vacuum C = 3.0 x 108m/s).
(3mks)
(ii) Show on the same diagram, the critical angle, c, and hence determine its value.
(3mks)
(iii) Given that r = 31.2°, determine the angle .
(3mks)
16. (a) State one difference between a transformer and an induction coil.
(1mk)
(b) State two energy losses in a transformer.
(2mks)
(c) A transformer has 1000 turns in its secondary coil and 10 turns on its primary coil. An alternating current of 2.5A flows
in the primary circuit when it is connected to a 12V a.c. supply.
(i) State the type of transformer.
(1mk)
(ii) Calculate the power input to the transformer.
(3mks)
(iii) Calculate the e.m.f. across the secondary coil.
(3mks)
(iv) Determine the maximum current that could flow in a circuit connected to the secondary coil if the transformer is 80%
efficient. (Use the e.m.f in secondary as calculated in (iii) above).
(3mks)
(v) In transmitting power why is it necessary to step up before transmission. Explain.
(2mks)
-
-
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
232/3
PHYSICS
PAPER 3 (PRACTICAL)
CONFIDENTIAL
Each candidate will require the following:
Q1.
Vernier calipers (to be shared)
A source of boiling water.
A glass beaker (200 – 250ml)
A thermometer (0 - 110°C)
A stop watch.
A magnifying glass.
A plastic measuring cylinder (100ml).
A circular cardboard plate with a hole to fit a thermometer
Q2.
Two new dry cells.
A cell holder.
A variable resistor (50) labelled K.
A carbon fixed resistor labelled R whose value is 10.
A voltmeter (0 – 3 or 0 – 5V).
An ammeter (0 – 1A).
A switch.
8 connecting wires, 2 with a crocodile clip at one end.
A piece of curtain rail, 20cm long bent into a semicircular curve until its diameter is 15cm.
- A glass marble.
- A stopwatch (the one used in question 1).
- A half metre rule.
NB: To make the curves curtain rails the teacher in charge of Physics may cut 20cm long pieces of the rail from the rails
available in hard waves.
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232/1,232/2,232/3 physics
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
232/3
Kenya Certificate of Secondary Education
PHYSICS
PAPER 3
(PRACTICAL)
TIME: 2½ HOURS
Question 1
You are provided with the following:
- A vernier calipers (to be shared).
- A source of boiling water.
- A glass beaker (250ml).
- A thermometer (0 - 110°C).
- A stopwatch.
- A magnifying glass.
- A plastic measuring cylinder (100ml).
- A cardboard circular plate with a hole.
Proceed as follows:
(a) Measures and record the room temperature R.
R = ……………………… °C.
(1mk)
(b) Using the vernier calipers provided, measure the internal diameter D of the glass beaker at its centre. (Position shown in
figure 1).
D = ……………………… m.
(1mk)
(c) Measure exactly 150ml of the hot water into the glass beaker and cover it with the cardboard plate. Place the beaker on a
wooden bench and insert the thermometer through the hole on the cover as shown in Figure 1.
(d) Measure and record the temperature  of the cooling water after every two minutes for at least 12 minutes (use the
magnifying glass provided to read the scale move accurately). Record the values of the temperature  in table 1 below.
(3mks)
Table 1
Time (min)
2
4
6
8
10
12
Temperature  (°C)
(e) Plot a graph of  (°C) against time t (min) on the grid provided.
(3mks)
(f) On the graph construct, as accurately as possible, five tangents at temperatures of 75°C, 70°C, 65°C, 60°C and 55°C. Find
the slope of each and record the value in table 2 below.
(5mks)
Table 2
75
70
65
60
55
Temperature  (°C)
( - R) (°C)
Slope of tangent
(°C minˉ¹)
(g) Plot a graph of slope

t

t
of tangents against temperature difference ( - R).
(h) Find the gradient of the graph.
(4mks)
(2mks)
SMC
where M is mass of water in kilograms, C is specific
A
D
heat capacity of water = 4200jkg¯¹K¯¹ and A the surface area of the beaker walls in contact with the hot water A  2
,
2L
(I) Determine the value of constant K from the graph given that K 
and S is the slope of the graph.
(1mk)
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232/1,232/2,232/3 physics
Question 2
You are provided with the following:
- Two dry cells.
- A cell holder.
- A variable resistor labeled K.
- A carbon fixed resistor labeled R.
- A voltmeter.
- An ammeter.
- A switch.
- 8 connecting wires at least two with a crocodile clip at one end.
- A curved curtain rail.
- A glass marble.
- A stopwatch.
- A half metre rule.
- Some plasticine.
PART A
Proceed as follows:
(a) Starting with the switch‘s open connect the circuit as shown in figure 2 below.
K
(b) Close the switch S and adjust the variable resistor K until the ammeter reading is 20mA. Record the corresponding voltmeter
(c) Repeat step (b) above for other values of ammeter readings and complete Table 3.
(6mks)
Table 3
I (mA)
20
40
60
80
100
120
I (A)
P.d (V)
(d) Plot a graph of I (A) against p.d (V) on the grid provided below.
(e) From the graph, determine
(i) the slope S.
(ii) State the quantity represented by the slope S and state its S.I units.
(iii) Value of resistor R.
PART B
Process as follows:
(f) Measure the diameter D of the semicircular curtain rail provided using the half metre rule (Figure 3 below).
D = ………………………. m
(5mks)
(2mks)
(2mks)
(1mk)
(1mk)
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232/1,232/2,232/3 physics
(g) Fix the lower end of the curtain rail on the bench using some plasticine as in Figure 3 above. Place the marble on one end of
the curtain rail and let it oscillate freely. Record the time t 1 taken by the marble to make 5 complete oscillations.
Repeat this 3 times and calculate the average time for 5 oscillations.
Complete table 4 below.
(1mk)
t1
t2
t3
t AVR 
t1  t 2  t 3
3
(h) Determine the periodic time T(S).
T = ………………………… (s).
(I) Given that
T  2
D
Determine the value of constant g.
2g
(1mk)
(1mk)
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
232/1 – PHYSICS PAPER 1 MARKING SCHEME
1. Mass of A = 0.8
Mass of B = 1 x 1000 = 1000g
Total mass

Total volume
1000  0.8 
0.96 

1000  

2.
3.
4.
5.
6.
0.96 (1000 + ) = 1000 + 0.8
 = 250cm³ 
High temperature and detergents lowers the surface tension of water. 
Glass is a poor conductor of  heat. In thick glass, there will be unequal expansion  but in thin glass heat if conducted
evenly.
Metal conducts heat away from the flame wood is a poor conductor. 
Liquid finds own  level. Height of water in the three tubes will be the same as Q. 
Series connection.
New K = ½ x 4  = 2N/m 
7.
8.
9.
Position of c.o.g should be as low as possible.
The pollen grain particles are hit by (invisible) water particle which are moving randomly.
Sum of clockwise moments = sum of anticlockwise moments
F x 1.6 = (1.6 + 2.4)300 
1.6F = 4 x 300
4  300
 750N
1.6
F
750
 = 3.5 x 105pa 
P

4
A 20  10
F
10. The balls rise up  the funnel.
11. Kinetic energy of  molecules increases therefore molecules move faster. There is a higher rate of collision  with the walls
of the container hence more force.
12. h = ½gt²
320 = 1/2 x 105t²
t=8
Range = Horizontal distance = Ut
50 x 8 = 400m
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232/1,232/2,232/3 physics
13.
14. Different gases expand to different extends when temperature increases hence occupy different volumes. Upthrust force
acting on he balloons will be different hence the change in equilibrium.
15. To minimize heat loss by radiation. 
SECTION B: (55 MARKS)
16. (a) (i)
Body must be less dense than water. 
(ii)
Body must displace weight of fluid equal to its own weight. 
The density of the body must be less than that of water or
Body must displace weight of fluid equal to its own weight.
(b) (i)
Volume of A displaced = 6 x 2 = 12cm³
Mass of A = V = 12 x 10-6 x 800 
Weight of A = Vg = 12 x 10-6 x 800 x 10 
= 0.096N 
(ii) Volume of B displaced = 6 x 3 = 18cm³
Mass of B = 18 x 10-6 x 1000
Weight = 18 x 10-6 x 1000 x 10
= 0.18N 
(iii) Total weight = 0.096 + 0.18 = 0.276N 
0.276
 0.0276kg 
10
0.0276

 = 657.14kg/m³ 
7  6  10 6
Mass 
17. (i) Melting point is 80°C.
(ii) t = 450 – 100 = 350 seconds. 
Q = Pt
= 100 x 350 
= 35000J 
(iii) Q = mlf 
35000 
(b)
(c)
18. (a)
(b)
(c)
100
lf
1000
lf = 350000Jkg¯¹ 
- Clay pot
- Sweating.
- Refrigerator.
- Surface area of the container.
- Humidity.
- Presence of wind.
Sponge reduces impulsive force by increasing the time of impact of force/or it help to spread the impact over a long time.
This reduces impulsive force.
Moving air exerts momentum in one direction.  To conserve the momentum the balloon shoots in the opposite direction
with a momentum equal to but opposite in direction to that of the air.
(i)
Total momentum = m1u1 + m2u2
= 150 x 10 + 100 x 0 
= 1500kgm/s 
(ii) Total momentum after collision = 1500kgm/s 
(iii) Momentum after collision = (150 + 100)V
1500 = 250V 
30 6
V 
1500
= 6m/s 
250
51
Page | 141
232/1,232/2,232/3 physics
(d) I
F 
(i)
2
MV

r

1 5
25

 50 N 
0.5
0.5
MV 2
T 
 Mg
r
2

II
= 50 – 1 x 10  Correct formula or correct substitution award 1mk
= 40N
MV 2
 Mg
III T 
r
= 50 + 1 x 10 Correct formula or correct substitution award 1mk
= 60N 
(ii)
At position B;  - The string is under highest tension at B. 
19. (a) (i)
V.R = 2
2
DE
2
Distance by DE = 2 x 2 = 4m
P.E = Mgh
= 10 x 10 x 2 = 200J 
(iii) Work done by effort = F x d
= 80 x 4 = 320J 
(ii)
 100 
Work done by effort
200

 100  62.5% 
320
Work done
Mgh
(b) Power 
 
Time
t
m  10  10
100 

30  60
(iv)
Efficiency 
m = 1800kg 
20. (i) Stirrer.  Source of heat
(ii) - Volume/length of air column.
- Temperature.
(ii) - Air is tapped by thin mercury thread in a capillary tube. The initial temperature of water is noted and the
corresponding volume. 
- The water is then heated and this in turn heats up the trapped air in the capillary tube. The volume of the air is read and the
temperature is recorded.
- Several values of temperature and corresponding volumes are recorded in a table.
- A graph of volume against absolute  temperature is drawn which is a straight line passing through the origin. 
- An increase in temperature leads to increase in volume. 
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232/1,232/2,232/3 physics
1.
2.
3.
4.
5.
6.
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
232/2 – PHYSICS PAPER 2 MARKING SCHEME
SECTION A: (25 MARKS)
When the switch is closed, the lamps are now in parallel, the resistance in the circuit reduces. ¹ A high current flows and the
fuse blows. ¹
Light travels in a straight line/
Rectilinear propagation of light. ¹
Magnified.
Upright/erect
Virtual
Any 2 x 1 = 2mks
The gold leaf becomes more positive as a result of attraction of the negative charge towards the metal cap.
(2mks tied)
Visible light.
0.1cm  25ms
6cm 
6  25
 1500 cs
0.1
=15cs ¹
T = 1.5s
f 
1
1
¹ 
 0.667H Z ¹
T
1.5
7.
A – It has a stronger magnetic field than B.
8.
Number of half-life

780
 3 ½
260
1st t 1
2nd
3rd
2
2  1020 
 1  1020 
0.5  1020 
0.25  1020
Atoms remaining after 3-half-life
= 2.5 x 1019 atoms ½
Atoms decayed
= (20 – 2.5) x 1019
= 17.5 x 1019
= 1.75 x 1020 atoms ¹
9. P-type semi-conductor is made by doping a pure-semi-conductor with group 3 atoms. ¹ The group impurity creates a hole
(positive) that attracts an electron for conduction. ¹
10. - Transverse waves forms crests and troughs as they propagate while longitudinal waves forms part of compression and
rarefaction. ¹
- Transverse waves moves perpendicular to the direction of wave motion while longitudinal waves moves parallel to the
direction of wave motion. ¹
11.
Alternative
t
Let the cliff be cm apart
Time for 1st echo = 3/2 in 1.5sec.
3
2
330
d
s
2 = 990
 = 495m ¹
2d
 V . ¹
t
2d
 330 . ¹
3  5
330  8
d 
2
= 1320m . ¹
Time for the second echo = 5/2 = 2.5sec.
1.5 + 25 = 4.0sec. ¹
D=5xt
= 330 x 4
= 1320m ¹
12.
Page | 143
232/1,232/2,232/3 physics
13. (a) The current flowing through the conductor is directly proportional to the potential difference across its ends provided
temperature and other physical conditions are kept constant.
(b) (i) When the switch is closed the current flows through the coil which offer resistance hence dissipating heat.
(ii) V = IR ¹
R
V 12
¹ = 4.8 ¹

I
25
(iii) Heat = Vlt ¹
= 12 x 2.5 x 60 ¹
= 1800J ¹
(iv) - Increasing the number of coils. ¹
- Increasing the current. ¹
(c) The readings will decrease because the resistance is decreased. ¹
14. (a) - Travel in straight lines at the speed of light.
- Cause ionization.
- Affect photographic films.
- They obey the equation V = f
(b) (i)
A – Cathode rays/fast moving electrons.
B – Anode.
(ii)
Change in heating current ¹ changes the number of electrons produced. ¹
(iii) Kinetic energy of the cathode rays is converted to heat energy.
(iv) Tungsten/molybdenum.
(v) T – Cathode.
(vi) To avoid collision between electrons and air molecules.
(c) eV = hf ¹
1.6 x 1019 x 24000 = 6.62 x 10-34 x f ¹
f 
1.6  10 19  24000
6.62 10 34
= 5.8 x 1018HZ ¹
15. (a) (i)
Dispersion of light.
(ii)
X – Red
Y – Violet
- Red has the lowest frequency/longest wavelength hence least deviated while violet has the highest frequency/shortest
wavelength hence most deviated.
(iii)
Act as point source of light.
(b) (i)
a
C
¹
V
3.0  108
¹

1.8  108
g 
= 1.6667 ¹
(ii) C on the diagram. ¹

1
1
1
 Sin C  
¹
Sin C
 1.6667
Sin C = 0.5999
C = 36.86° ¹
(iii)
Sin 
 a  g ¹
Sin r
Sin  = 1.6667 x 31.2 ¹
= 0.8634
 = 59.7° ¹
16. (a) A transformer uses alternating current while an induction coil uses interrupted direct current.
(b) Flux leakage.
Resistance of coil
Eddy currents.
Hysteris loss
(c) (i)
Step – Up transformer
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232/1,232/2,232/3 physics
PP = IPVP ¹
= 2.5 x 12
= 30W
(ii)
NS
 V P ¹
NP
1000

 12 ¹
10
VS 
(iii)
= 1200V ¹
PS 
(iv)
80
 30  24W
100
24 = IS x 1200
IS 
24
1200
= 0.02A
(v) - Minimizing energy losses.
- Stepping up lowers the current hence minimizing energy losses.
1.
KAHURO/MURANG’A EAST JOINT EXAMINATION – 2016
232/3 – PHYSICS PAPER 3 MARKING SCHEME
(a) R = °C
(1mk)
(b) D = 0.05m
(1mk)
(d) Completing table
Each value
(½mk)
Total
(3mks)
(e) Plotting
(2mks)
Smooth curve
(1mk)
(f) Table 2
(½mk) per entry
Total (5mks)
(g) A graph of slope /t against temperature difference ( - R).Plotting (2mks)
Straight line (1mk)
Scale
(1mk)
Straight line through the origin.
2.
 t
= __________ (1mk)
   R
Table 3
I(mA)
20
40
60
80
100
120
I(A)
0.02
0.04
0.06
0.08
0.10
0.12
p.d(V)
0.2
0.4
0.6
0.8
1
2
(d) Graph of I (A) against p.d (V).
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R
1
1

10 
Slope 0.1
Part B
D = 15cm
= 0.15m
t one
S
2D
T2 
2g
2D
2g 
T2
2D 2  0.15
g 

2T 2
2T2
T 
NANDI NORTH AND NANDI CENTRAL SUB-COUNTIES JOINT EXAMINATIONS 2016
Page | 146
232/1,232/2,232/3 physics
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15.
Kenya Certificate of Secondary Education (KCSE)
232 / 1
PHYSICS
PAPER 1
TIME: 2 HOURS
SECTION A (25 MARKS)
Answer ALL questions in this section in the spaces provided
The micrometer screw gauge represented by figure 1 has a thimble scale of 50 divisions.
(1mk)
The bar AB represented in figure 2 has negligible weight and is pivoted at A.
Find the weight W when the bar is equilibrium.
(3mks)
Explain why a glass container with thick walls is more likely to crack, than one with a thin wall when a very hot liquid is
poured into them.
(1mk)
Two identical alluminium rods are placed as shown in figure 3. One rests on a metal block and the other on a wooden block.
The protruding ends are heated on a Bunsen burner as shown.
State with a reason on which bar of the wax is likely to melt sooner.
(2mks)
A spring stretches by 5cm when 40N force is applied to it. If the 40N force is replaced by 125N, how much further would the
spring stretch?
(3mks)
(a ) A body in circular motion moving at constant speed is said to be accelerating. Explain this.
(1mk)
(b) A stone of mass 450g is rotated in a vertical circle at 3 revolutions per second. If the string has a length of 1.5m,
determine its linear velocity.
(2mks)
State the variable force acting on a ball bearing released to fall freely on a surface of glycerin.
(1mk)
Figure 4 shows a manometer used to measure the pressure of gas.
The force exerted by gas on A is 20,000N. Calculate the density of the liquid given that the cross-sectional area of A is 0.1m2
and the atmospheric pressure is 100,000 Pascals.
(3mks)
State the Newton‘s second law of motion.
(1mk)
A trolley of mass 4kg is moving with a velocity of 3m/s and collides head on with another trolley of mass 2kg travelling in
the opposite direction a velocity of 4m/s. After collision both trolleys fuse and move with a common velocity V. Determine
V.
(2mks)
Water flows through a horizontal pipe of varying cross-sectional area as shown in figure 5.
The volume flux is 30m3/s. calculate the change in speeds of the fluid.
(3mks)
In an experiment to determine the density of ground stones a form one student obtained the following results
Mass of empty density bottle – Xg
Mass of density bottle filled with water – Yg
Mass of density bottle + ground stones – Vg
Mass of density bottle + ground stones + top up water – Zg
Use the information to calculate the density p of the ground stones.
(3mks)
SECTION B: 55 MARKS
ANSWER ALL QUESTIONS IN THIS SECTION.
(a)Using the kinetic theory of gases, explain how rise in the temperature of a gas causes a rise in the pressure of the gas if the
volume is kept constant.
(2mks)
(b) Figure 6 below shows a set up that may be used to verify Charles‘ law.
(i) State the measurements that should be taken in the experiment.
2mks
(ii) Explain how the measurement taken in (i) above, may be used to verify Charles Law.
(4mks
(c) A certain mass of hydrogen gas occupies a volume of 1.6m3 at a pressure of 1.5x105 pa and temperature 12°C. Determine
its volume when the temperature is O° at a pressure of 1.0x10 5pa.
(3mks)
(a)State the law of floatation.
(1mk)
(b)The figure 7 below shows a simple hydrometer.
(i) State the purpose of the lead shots in the glass bulb.
1mk
(ii) How would the hydrometer be made more sensitive?
1mk
(iii)
Describe how the hydrometer is calibrated to measure relative density.
2mks
(c) Figure below shows a cork floating on water and held to the bottom of the beaker by a thin thread.
(i) Name the forces acting on the cork.
(3mks)
(ii) Describe how each of the forces mentioned in (i)above changes when water is added into the beaker until it fills p.
(3mks)
An engineer uses a pulley with a velocity ratio of 6 to raise an engine out of a vehicle. The engine which has a weight of
3200N is raised through a vertical distance of 1.5m by the machine. If the machine pulls within an effort of 600N, calculate:(i) The work done by the machine.
(3mks)
(ii) The work done by effort.
(2mks)
(iii) The efficiency of the machine.
(3mks)
(iv) State two reasons why the efficiency in (a) (iii) above is not 100%.
(c) (i) State the law of conservation of energy.
(2mks)
(1mk)
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(ii) The graph shown below shows how potential energy of a stone thrown vertically upwards varies with height.
Sketch on the same axes the graph of kinetic energy against height.
(1mk)
16. (a) Differentiate between specific heat capacity of ice and specific latent heat of ice.
(1mk)
(b) Figure 9 shows an incomplete circuit set-up by a student to determine the specific capacity of an Alluminium block of
mass 1.4kg.
(i) Complete the diagram showing missing components in their correct symbols.
(2mks)
(ii) During the experiment, the heater was switched on for 15 minutes. The ammeter and voltmeter were found to be
steady at 3A and 48V respectively. The temperature rose by 250C. Calculate the specific heat capacity of the
Aluminum block.
(4mks)
(iii) Give two precautions which should be taken in when carrying out the experiment so as to obtain accurate results.
(2mks)
17. (a) A body in motion is uniformly retarded from a certain velocity to a final velocity V in a time of t seconds.
(i) Sketch a velocity time graph to show the motion.
(1mk)
(ii) Using the drawn graph show how to get the final velocity V.
(2mks)
(iii) By finding the area under the graph, show that the total displacement for the motion is given by s = ut + ½ at 2.
(3mks)
(b) A stone of mass 0.5kg is whirled in a vertical circle by a cord of length 1.5m at a velocity of 30m/s. Find the maximum
tension on the cord.
(3mks)
(c) Speed governor is one of the applications of circular motion. Explain how it works.
(3mks)
NANDI NORTH AND NANDI CENTRAL SUB-COUNTIES JOINT EXAMINATIONS 2016
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232/1,232/2,232/3 physics
1.
2.
3.
Kenya Certificate of Secondary Education (KCSE)
232 / 2
PHYSICS
PAPER 2
TIME: 2 HOURS
SECTION A (25 MARKS)
Answer ALL questions in this section in the spaces provided
Name two measurements you would need to determine whether a lead accumulator is fully charged.
(2mks)
Fig. 1 shows a ray of light striking a mirror at an angle of incidence of 45 0. Complete the diagram to show the path of the ray
and the angle of reflection at which it leaves the second mirror.
(2mks)
Figure 2 shows a straight electrode placed near a point charge. Draw the electric field map between them.
Figure 3 shows an electric circuit operated by four dry cells each of e.m.f 1.5V and internal resistance of 0.2Ω. When the
switch is closed, the ammeter reads 0.2A.
(3mks
5. The graphs in figure 4 represents the same wave.
Determine the velocity of the wave.
(3mks)
6. Arrange the following waves in order of increasing frequency; X-rays, visible light, infrared, T.V waves, microwaves,
ultraviolet, y-rays.
(1mk)
7. Two heaters A and B are connected in parallel across a 240V mains supply. Heater A is rated 1000W and B 2500W.
Calculate the ratio of their resistances.
(3mks)
8. Draw a circuit showing a junction diode in a reverse bias connection to a cell.
(2mks)
9. Find the cost of using a 3000W electric heater for 24 hours. The cost of a unit is sh. 2.00.
(2mks)
10. Figure 5 below represents a soft iron bar being magnetized.
4.
Magnetic force
Fig. 5
Explain the shape of the graph.
(1mk)
11. A gun is fired in front of a high building. It takes 2 seconds for the soldier to hear the echo. If the speed of sound in air is
330m/s. Calculate the distance from the building which the soldier stands.
(2mks)
12. Two monochromatic rays from a ray box are incident on a glass prism of refractive index 1.56 as shown in the figure below.
450C
Draw on the diagram how the rays are refracted until they leave the prism.
(2mks)
13. What is the purpose of a commutator in an electric current?
(1mk)
SECTION B (55 MARKS)
14. (a) A Television tube uses a voltage of 4.55k.V to accelerate electrons released from its cathode by thermionic emission.
(i) What is meant by thermionic emission?
(1mk)
(ii) If the electron has a charge of -1.6 x 10-19C and the mass of an electron is 9.1 x 10 -31kg, find:I.The energy of an electron striking the television screen.
(3mks)
II The speed of the electron as it strikes the screen.
(3mks)
(b) Figure 7 shows a cathode ray oscilloscope.
(i) State the function of the components labeled A, B, C and D.
(4mks)
(ii) Sketch what will be observed on the screen when an A.C voltage is connected to the Y-plates.
(1mk)
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15. (a) Figure 8 below represents an eye defect.
(i) State two possible causes of the defect.
(2mks)
(ii) Draw a ray diagram to show how the defect can be corrected.
(1mk)
(b) An object O placed in front of a converging lens Lo forms an image I on the other side of the lens. Another
Converging lens Le is placed such that the two form a compound microscope.
(i) Draw a ray diagram of the set up to show how the final image is formed.
(3mks)
(ii) State the reason why the focal length of Lo must be greater than that of Le.
(1mk)
(c) An object is placed 20cm from a converging lens. A focused image is formed on a screen placed 30cm from the lens on
the other side. If the screen is moved 6cm towards the lens, work out the distance the object must be moved for the
image to be formed on the screen.
(3mks)
(1mk)
(b) The graph below shows radioactive decay of iodine.
Graph
Use the graph to determine the half-life of iodine.
(2mks)
(c) Figure 9 below shows a G.M tube.
Diagram
(i) Give the reason why the mica window is made thin.
(1mk)
(ii) Explain how the radiation entering the tube is detected by the tube.
(3mks)
(iii) What is the purpose of the halogen vapour?
(1mk)
(d) A sample of a radioactive substance of half life 1500 years has an activity of 32000 counts per hour. Find the time it will
take for the activity to decrease to 2000 counts per hour.
(3mks)
17. Figure 10 shows UV light shone on a zinc plate placed on a negatively charged leaf electroscope. It was observed that the leaf
collapses.
Diagram
(a)
State and explain the above observation.
(2mks)
(b) Figure 11 below shows a photocell.
(i) State the reason of using an evacuated photocell.
(1mk)
(ii) Explain the role of resistor P in the circuit.
(1mk)
(iii) What is the effect on the reading of the millimeter if the frequency of the radiation falling on the cathode is
increased?
(2mks)
(iv) Briefly explain how the set up can be used as an automatic switching device alarm.(2mks)
(c) A surface whose work function is 1.82 x 10-19J is illuminated with light of frequency
4.0 x 10 14HZ. Work out
-34
the minimum kinetic energy of the emitted photoelectrons. (h = 6.6 x 10 Js)
(3mks)
18. (a) State one cause of energy losses in a transformer and explain how it can be minimized.
(2mks)
(b) A transformer is designed to supply a current of 7.5A at a potential difference of 100V to a motor from an A.C supply
of 240V. If the efficiency of the transformer is 85%, calculate;(i) The power supplied to the transformer.
(3mks)
(ii) The current in the primary coil.
(3mks)
(c) Fig. 12 below shows a cross-section of a bicycle dynamo. The wheel is connected by an axle to a permanent cylindrical
magnet and is rotated by the bicycle tyre.
(i) Explain why the bulb lights.
(2mks)
(ii) How can the bulb be made brighter?
(1mk)
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232/1,232/2,232/3 physics
NANDI NORTH DISTRICT JOINT MOCK 2013
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232/3 – PHYSICS PAPER 3
CONFIDENTIAL
QUESTION 1
Two dry cells (Size D, each 1.5V)
Nichrome Wire (SWG 28 – 100cm long mounted on a mm scale).
An ammeter.
Cell holder.
6 connecting wires with crocodile clips.
Switch.
A Voltmeter
A Jockey (Crocodile clip)
QUESTION 2
A metre rule.
One Stop watch.
One complete stand.
One spring, (spring constant 0.1N/cm) Range 0.07 – 0.12Ncm-1
2 pieces of wood.
Beam balance or electronic balance (to be shared).
One 100g mass labeled M.
NANDI NORTH AND NANDI CENTRAL JOINT EXAMINATIONS 2016
Kenya Certificate of Secondary Education (KCSE)
232 / 3
PHYSICS
PAPER 3
(PRACTICAL)
JULY / AUGUST 2016
TIME: 2 ½ hours
1. You are provided with the following: Nichrome wire (SWG 28) mounted on a mm scale.
 Micrometer screw gauge (to be shared).
 Voltmeter (0 – 3V or 0-5V)
 Ammeter (0-1A)
 Switch
 Jockey / long wire with crocodile clip attached.
 One new dry cell and a cell holder.
 6 connecting wires with crocodile clips attached to one end.
Proceed as follows:
i. Set up the circuit below and ensure that when the switch is open, both meters read zero, keep the switch open when readings
are not being taken.
Diagram
(i) Measure and record the diameter d of the nichrome wire AB mounted on a mm scale using the micrometer screw gauge.
(1mk)
d = ……………………………………..mm = ………………………………….m
(ii) Disconnect the jockey from wire AB and close the switch. Record the value E of the voltmeter reading.
E = ……………………………………………. V
(1mk)
ii. Now, connect the jockey on AB at a distance L = 2.5cm. Close the switch and record the voltmeter and ammeter readings, V
and I respectively in table 1 below.
Table 1
L(cm)
2.5
7.5
10.0
20.0
30.0
40.0
P.d(V)
Current I (A)
IV (watts) 4d.p
(i) Complete the table
(6mks)
(ii) Plot a graph of IV (Vertical axis) against L.
(5mks)
(iii) Using your graph, find the value Lo where the line intersects the horizontal axis. (1mk)
Lo = ………………………………….cm
iii.
Now, place the jockey on AB such that the length l is 63cm. Close the switch and record both the voltmeter reading, V
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232/1,232/2,232/3 physics
V=
__________________________ V
I =
__________________________ A
Determine the value r from the relation.
iv.
r
(2mks)
(2mks)
E V
I
v. Determine the value of X from the relation:
r





a.
b.
c.
d.
rd
f.
2.52
where π= 3.142
Question 2
2. PART A
You are provided with the following:Vernier calipers
Micrometer screw gauge
Masses: one 10g, two 20g and one 100g.
A helical spring.
Metre rule or half metre rule.
Proceed as follows:
Determine the number of complete turns of the helical spring.
N = ___________________________
Measure the external diameter of the spring using the vernier calipers.
D = ___________________________m.
Use the micrometer screw gauge to determine the diameter of the wire of the spring.
d = _________________________ m
Determine the value of m.
N
e.
(2mks)
2
(1mk)
(1mk)
(1mk)
0.4 D
dm
Suspend the helical spring vertically alongside the clamped half metre rule as shown in figure 3 below. Determine the length
Lo = ______________________ cm
Load the spring with a mass of 20g and determine the new reading on metre rule, (L). Record this in the table below.
Determine the extension e = L – Lo due to the mass of 20g and record the value in the table given below. Repeat step (f) for
other masses and complete the table.
(6mks)
Mass(g)
0
20
30
40
50
60
70
80
90
100
Weight (N)
Extension e (cm)

1
cm 1
e


1
cm 1
e

g.
Plot a graph of weight (N) against
h.
Determine the slope S of the graph at a mass of 55g.
i.
Given that m 
255T
, determine the value of T.
S2
(5mks)
(2mks)
(2mks)
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NANDI EAST, NANDI SOUTH & TINDERET SUB-COUNTIES JOINT EVALUATION 2016
1.
2.
Kenya Certificate of Secondary Education (KCSE
232 / 1
PHYSICS
PAPER 1
THEORY
JULY / AUGUST 2016
TIME: 2 HOURS
SECTION A (25 MARKS)
Answer ALL questions in this section in the spaces provided
Figure 1 below shows a section of a micrometer screw gauge used by a student to measure the diameter of a wire.
Determine the cross-sectional area of the wire.
(2mks)
Figure 2 below shows a capillary tube placed in a trough of mercury.
8.
Give a reason why the level of mercury in the tube is lower than in the beaker.
(1mk)
Body scanners and lasers are applications of physics in medicine. State one other application.
(1mk)
A piece of sealing wax, weighs 3N in air and 0.22N when immersed in water. Calculate the density of the wax.
(2mks)
The barometric height in a town is 65cmHg. Given that the standard atmospheric pressure is 76cmHg and the density of
mercury is 13600kg/m3, determine the altitude of the town. (Density of air is 1.25kg/m 3)
(2mks)
When the temperature of a gas in a closed container is raised, the pressure of the gas increases. Explain in terms of kinetic
energy how the molecules of the gas cause an increase in pressure.
(2mks)
A certain mass of hydrogen gas occupies a volume of 1.8m3 at pressure of 2.5 x 105 N/M2 and a temperature of 270C.
Determine the volume when the temperature 00C at a pressure of 7.5 x 104 N/M2.
(3mks)
The figure below shows a uniform metal rod of mass 100g balanced over a pivot using a spring balance and a mass of 300g.
9.
Calculate the tension in the spring.
A student below air into a horizontal straw in the direction shown in the diagram below.
3.
4.
5.
6.
7.
(3mks)
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232/1,232/2,232/3 physics
State what was observed in the vertical straw.
(1mk)
10. The figure below shows a spring balance, its spring constant is 225N/m. The scale spreads a distance of 20cm.
Determine the maximum weight that can be measured using the spring balance.
(2mks)
11. Give a reason why water is not a suitable liquid for use in a barometer.
(2mks)
12. An oil drop of radius 0.42mm when placed in water spreads out to form a circular patch of radius 42cm. using this
information:
a. Estimate the size of the oil molecule.
(2mks)
(1mk)
13. An object is fired vertically upwards from the ground level with a velocity of 50m/s and reaches a maximum height h. It
falls back to the ground. Sketch velocity time graph to represent the motion of the object from the time it is fired till it hits
the ground.
Time,t (s)
SECTION B (55 MARKS)
Answer ALL questions in this section on the spaces provided.
14. (a) State two factors that affects conductivity in metals.
(2mks)
(b) You are provided with a metallic ball, a metallic ring and a source of heat. Describe how you would show that solids
expand.
(3mks)
(c) Figure below shows how water expands from lower temperatures.
0
4
On the axes below sketch a graph of density against temperature.
Temperature (0C)
Temperature 0C
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(d) Explain briefly why concrete walls are reinforced with steel and not other metals.
15. Figure below shows a wheel and axle of radius R and r respectively.
R
.
r
(1mk)
(a) Show that the velocity ratio of the system is given by 
(2mks)
(b) Given that r = 5cm, R = 20cm and an effort of 1200N is used to lift a load of 3000N. Determine:
i.
The work done by effort to raise the load through a distance of 2m.
ii.
The efficiency of the system.
iii.
State two ways in which the efficiency in (ii) above can be increased.
(c) A stretched spring with a load attached to one end and fixed at the other is released as shown below.
(3mks)
(3mks)
(2mks)
Sketch on the same axis below the graph of potential energy and kinetic energy with time(2mks)
Potential energy
16. (a) State any two factors that affect the melting point of a liquid.
(2mks)
(b) 600g of a solid X was heated by an electric heater rated 500W until it melted, temperature readings taken as it heats
from room temperature. The graph shown below shows variation of temperature against time.
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232/1,232/2,232/3 physics
0
Graph of Temperature C against time (minutes)
1.
2.
From the graph, determine the melting point of the solid X.
I. Determine the heat supplied by the heater for solid X to melt.
II. Hence determine the specific latent heat of fusion for solid X.
I. State the room temperature.
II. From the graph, determine the temperature change between the time t = 0 minutes and t = 4.0 minutes.
3.
(1mk)
(2mks)
(2mks)
(1mk)
(2mks)
III. Hence determine the specific heat capacity of the solid X.
(3mks)
17. (a) State two factors that influence fractional force between two surfaces.
(b) Figure below shows a rectangular block of wood attached o a spring balance being pulled gently by a pulling force P
i.
A graph of pulling force against time was drawn as shown below.
FB
FA
P
Q
Time
State the forces FA and FB.
FA :……………………………………………………………….
(1mk)
FB :……………………………………………………………….
(1mk)
II. From the graph, state what happens to the block of wood between point P and Q.
(1mk)
Given that the wooden box has a mass of 2.0kg and requires force of 5N to pull it with uniform speed along a horizontal
surface, calculate the coefficient of friction between the surface and the block. Take (g = 10N/kg).
(3mks)
I.
ii.
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232/1,232/2,232/3 physics
(c) Figure below shows a steel bearing moving through glycerine at a steady velocity.
Steel ball bearing
Glycerin
Tall measuring cylinder
Indicate on the diagram the forces with directions acting on the ball bearing.
(2mks)
18. (a) A body moving in a circular path with constant speed is said to be accelerating. Explain.
(1mk)
(b) A stone of mass 40g is tied to the end of a string 50cm long such that it is 10m above the ground at its lowest as shown
in the diagram.
The stone is whirled in a vertical circle at 2 rev/s.
I. (i) If the string breaks at point B, what is the velocity at this level?
(2mks)
(ii) Determine the maximum horizontal distance it travels after breaking.
(3mks)
II. Calculate
i.
The tension in the string at point B.
(3mks)
ii.
The tension in the string at point A.
(2mks)
(c) State one application of Uniform Circular motion.
(1mk)
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232/1,232/2,232/3 physics
NANDI EAST, NANDI SOUTH & TINDERET
SUB-COUNTIES JOINT EVALUATION 2016
4.
Kenya Certificate of Secondary Education (KCSE)
232 / 2
PHYSICS
PAPER 2
THEORY
JULY / AUGUST 2016
TIME: 2 HOURS
SECTION A: 25 MARKS
Answer all questions from this section.
A plain sheet of paper and a plane mirror both reflect light yet only the plane mirror forms images. Explain why the paper
cannot form images.
(2mks)
The element of an electric hot plate has a resistance of 120Ω. What is the energy dissipated when element is kept on for 10
minutes on a 240V supply?
(2mks)
Arrange the following in order of increasing wavelength: Visible light, X-Ray, Ultra Violet Radiation and Radio Waves.
(1mk)
In the circuit shown below, the battery has an e.m.f. of 6.6V and internal resistance of 0.3Ω.
5.
Determine the reading of the ammeter.
The figure below shows the image formed when an object is placed in front of a concave lens.
1.
2.
3.
6.
7.
8.
(3mks)
Using suitable rays, locate the position of the object.
(3mks)
State the major difference between a dry cell and a wet cell.
(1mk)
226
Ra disintegrates into a new stable element lead 206 Pb. How many Alpha and Beta particles are emitted?
88
82
(2mks)
The figure below shows an arrangement of three components. If the total capacitance of the capacitors is 5μf, determine the
value of X.
(3mks)
9. Explain why a concave mirror is used as a shaving mirror.
(1mk)
10. A ferromagnetic material was magnetized using single stroking method. Sketch a graph to show how the strength of the
magnet being created varies with the number of strokes.
(2mks)
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232/1,232/2,232/3 physics
11.
Identify and explain two faults in the light circuit shown in the figure above.
12. The figure below shows two conducting wires A and B passing through a horizontal piece of cardboard.
(2mks)
(a) Sketch the resultant magnetic field patterns when the currents of the high magnitude are flowing in both wires as
shown.
(1mk)
(b) What is the resulting effect of the field on the wires at the loose ends?
(1mk)
13. State one property of high quality X-rays.
(1mk)
SECTION B: 55 MARKS
Answer all the questions from this section.
14. (a) The figure below shows the cross-section of a ripple tank full of water. a piece of cork floats
on the surface of water and a straight edge vibrator placed at shallow end A to generate waves that travel to deep end B.
1.
2.
3.
4.
Name the type of wave generated on the water surface.
(1mk)
The cork is observed to stay put despite passing water waves. Explain this observation.
(2mks)
It was estimated that successive waves pass the cork every 0.25 seconds. If the speed of the waves is 0.28m/s, determine
the frequency and wave length of the waves at that point.
(4mks)
In the space provided, sketch the wavelength as viewed from a point above the ripple tank.
(1mk)
A
B
(c)
A ship sends out an ultrasound whose echo is received after 10 seconds. If the wavelength of the ultrasound in water is
0.05m and the frequency of the transmitter is 50KHz, determine the depth of the ocean.
15. (a) The diagram below shows a narrow beam of white light onto a glass prism.
1.
2.
3.
4.
What is the name of the phenomenon represented in the diagram?
Name the colour at X and Y.
What is the purpose of the slit?
(1mk)
(2mks)
(1mk)
(1mk)
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232/1,232/2,232/3 physics
(d) The figure below shows the path of a ray of light passing through a rectangular glass block placed in air.
1. Determine the refractive index of glass.
2. Given that speed of light in air 3.0 x 108m/s, find the speed of light in the glass.
16. (a) What do you understand by the term mutual induction?
(b) State two factors that determine the magnitude of e.m.f. induced in a coil.
(c) The diagram below shows an induction coil used to produce sparks.
(2mks)
(2mks)
(1mk)
(2mks)
1. Name the parts labeled A, B and C.
(3mks)
2. Explain the purpose of device C.
(1mk)
(d) A transformer is used on a 240V A.C. supply to deliver 12A at 120A to a hating coil. If 20% of energy taken from the
supply is dissipated in the transformer.
(i) What is the current in the primary coil?
(3mks)
(ii) Give two causes of 20% energy dissipation in the transformation above.
(2mks)
17. In an experiment to find the relationship between frequency of radiation and kinetic energy of photoelectrons in a
photoelectric device, the following graph was obtained.
Use the graph to answer the following questions.
(e) (i)
Determine the threshold frequency.
(1mk)
(ii) Find the plank‘s constant h.
(3mks)
(Take the charge of an electron to be .6 x 10 -19C)
(iii) Determine the work function of the metal in joules.
(2mks)
(f) Determine the threshold wavelength of a metal whose work function is 2.4 x 10 -18J. (3mks)
(Take the plank’s constant to be 6.63 x 10-34Js)
(g) An alternating voltage of peak value 15V and frequency 25Hz is applied to the terminals of a cathode ray oscilloscope. The
Y-gain is set at 5v/cm and the time base at 10ms/cm. Draw the trace observed on the screen.
(3mks)
1cm
18. (a) What is an extrinsic semi conductor?
(b) The figure below shows a PN junction diode used in a rectifier.
(1mk)
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232/1,232/2,232/3 physics
1.
2.
3.
4.
What type of rectification is shown?
Describe how the rectification is achieved.
State two disadvantages of this rectification.
In the space provided below, sketch the output signal displayed on the CRO during the rectification process.
(1mk)
(3mks)
(2mks)
(2mks)
NANDI EAST, NANDI SOUTH & TINDERET SUB-COUNTIES JOINT EVALUATION 2016
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232/3
PHYSICS PRACTICAL
JULY / AUGUST 2016
CONFIDENTIAL INSTRUCTIONS TO SCHOOLS
Each student should be provided with the following apparatus:Question 1
Two dry cells (size D)
One bulb (1 – 3V)
Voltmetr (0 – 3V or 0 – 5V)
Ammeter (0 – 2.5A)
A mounted nichrome wire (swg) on millimeter scale and labeled X and Y.
Switch
Seven connecting wires at least two with crocodile clips.
Micrometer screw gauge (to be shared)
Question 2
One metre rule
Two knife edges each of height 20cm
An optical pin to act as a pointer
Some cellotape
One half metre rule
One 400g mass or 100g x 4
One complete stand and clamp
Vernier calipers (to be shared)
One concave mirror of focal length 10cm
One mirror holder
One white screen
NANDI EAST, NANDI SOUTH & TINDERET
SUB-COUNTIES JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (KCSE)
232 / 3
PHYSICS
PAPER 3
(PRACTICAL)
JULY / AUGUST 2016
TIME: 2 ½ hours
You are provided with the following:Two dry cells (size D)
One bulb
Voltmeter (0 – 3V or 0 – 5V)
Ammeter (0 – 2.5A)
A Nichrome wire mounted on a millimeter scale
Switch
Seven connecting wire at least two with crocodile clips
Micrometer screw gauge
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232/1,232/2,232/3 physics
Proceed as follows:
(i) Set up the circuit as shown in figure 1.
ii) With the crocodile clip at X read and record the voltmeter reading, V and the ammeter reading I in table 1 below. Repeat this
procedure for the lengths, L = 80, 60, 40, 20 and 0 respectively.
Table 1
Length, L(cm)
100
80
60
30
40
20
0
Voltage V(v)
Current, I(A)
Resistance, R 
V
 
I
(iv) Plot a graph of the ammeter reading (y = axis) against voltmeter reading.
(5mks)
(v) Determine the slope of your graph at V = 0.45 volts.
(2mks)
(vi) What physical quantity is represented by the slope of the graph at any given point?
(1mk)
i.
(i) Given the apparatus in a (i) above, draw a diagram of a circuit you would use to determine the current through the
resistance wire and the potential difference across it.
(2mks)
i.
Set up the circuit you have drawn. Record the ammeter reading, I and the voltmeter reading V, when L = 100cm.
V = ………………………………………..v
(1mk)
I = …………………………………………A
(1mk)
ii.
Using a micrometer screw gauge, measure the diameter, d, of the nichrome wire.
d = …………………………………………m
iii.
Calculate the quantity, p = 0.785 
2
V   d

 
I  L
2.










a.
A. You are provided with the following:A metre rule
Two knife edges
An optical pin to act as pointer
Some cellotape
One half metre rule
400g mass or 4 x 100g masses
Complete retort stand
Vernier calipers
Proceed as follows:
(i) Measure the width, d and the thickness, t of the metre rule provided using the vernier calipers.
d = ………………………………………….m
t = ………………………………………….m
(ii) Given that M 
b.

 where L = 100cm.

(1mk)
(2mks)
(1mk)
(1mk)
td 3
Calculate the value of M.
12
(i) Attach a pointer (optical pin) at the 50cm mark of the metre rule provided using the cellotape
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232/1,232/2,232/3 physics
i.
ii.
iii.
Place the metre rule so that it lies horizontal on the two knife edges (wedges) provided.
Clamp the half metre rule vertically and place it near the 50cm mark of the metre rule, and adjacent to the pointer as
shown in the diagram 2(a) below.
Place the metre rule on the knife edges such that the distance, L, between them is equal to 90cm and is equidistant from
the 50cm mark of the metre rule as shown in figure 2(a).
iv. Read and record the initial position of the pointer on the half metre rule.
Note: The 0cm mark on the half metre rule should be on top, at the clamped end of the half metre rule and the 50cm mark is
below.
c. Suspend a mass of 400g at the 50cm mark of the meter rule using a thread.
d. Read and record the final position of the pointer, L1, on the half metre rule. Hence find depression, y = L1 – L0, of the metre
rule as shown in figure 2(b). record the results in table.
e. Remove the mass from the meter rule. Repeat the procedure b(iv) to d above for values of L equal to 80cm, 70cm, 60cm,
50cm and 40cm.
f. Enter your results in table 2 below.
L(cm
90
80
300
70
60
50
40
Final pointer position, L1(cm)
Depression, y = L1 – L0(cm)
Log L
Log y
(6mks)
g. Plot a graph of log y (y-axis) against log L.
(4mks)
h. Find the slope S of the graph.
(2mks)
i.
Given that
E
1
determine the value of E.
4.5S
(2mks)
2. B
You are provided with the following: A concave mirror
 A mirror holder
 White screen
 A metre rule.
Proceed as follows:j. Arrange the concave mirror, mirror holder and the white screen as shown in figure 2(c) below.
Move the concave mirror towards the white screen ………………… clear image of the tree or any far object is seen on the
screen.
l. Measure the distance, h1, between the mirror and the white screen.
h1 = ………………………….m
(½mk)
m. Repeat procedure (b) and (c) to get another value of h1 and record it as h2.
h2 = ………………………….m
(½mk)
n. Calculate, h, the average value of h1 and h2.
h = …………………………..m
(1mk)
k.
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232/1,232/2,232/3 physics
1.
NANDI EAST, NANDI SOUTH & TINDERET SUB-COUNTIES JOINT EXAMS 2016
232/1 – PHYSICS PAPER 1 - MARKING SCHEME
16.32
 8.16mm
2
A  r 2  77  8.16 2
A  209.1848mm 2 √
r
2.
3.
Greater cohesive√ force between mercury molecules than adhesive force between mercury and glass molecules.
- X-Ray
- Ultra sound
(any one)
- Magnetic resonance
U  3  0.22  2.78N
WA
U
√
3
R.d 
 1.07913669
2.78
S  R.d   water
P   gh, 76  65   11cmHg
R.d 
4.
5.
6.
  1.07913669 100
 1079.13669kg / m 3
√
0.11 x 13600 x 10 = 10 x 1.25 x h√
h = 1196.8m√
Rise in temperature increases the kinetic energy and speed√ of gas molecules. This increases the rate of collision of gas
molecules and wall of container which results to a higher rate of change of√ momentum.
P2V2
P1V1
=
√
T2
T1
2.5  105  1.8 7.5  10 4  V2

27  273
273
5
2.5  10  273
V2 
 3.03m 3
4
300  7.5  10
7.
Sum of clockwise moments = sum of anti-clockwise moments.
T  20  (30  1)  50  3 √
8.
20T = 30 + 150
20T = 180
Water rises upwards √
9.
e
T
180
 9N √
20
20
 0.2
100
F =
ke = 225 x 0.2√
= 45N√
10. Low density √
11. (a) Volume of drop = patch area x thickness
t
4
3
  0.42 
7
3
= 5.6  10 mm
2
 420 
(b) - Oil drop is spherical;
- Oil does not evaporate; (Total = 2mks)
SECTION B
12. (a) - Length of conductor
- Nature and type of material
- Thickness of conductor
- Time taken
(any two)
(Total 2mks)
Page | 164
232/1,232/2,232/3 physics
-
(b) - Hold the ring by the handle. Try to fit the metallic ball before and after heating in turn and observe√1
Observation
The ball just passes through the ring when cold but when heated for sometime it does not pass trough. √1
Conclusion
The heated ball does not go through the ring since the ball has expanded. √1
(Total 3mks)
(c)
√1
√1
4
Temperature (0C)
(d) - Expand and contract at almost equal rate. √(1mk)
13. (a) In one complete revolution.
Load moves through distance 2 r
Effort moves through distance 2 R
0
But V.R.=
(b) I.
II.
III.
Effortdistan ce 2R
R
√1=
√1

r
Workdone
=
Efficiency
=
M.A
=
V.R
=
=
Force x distance√1
1200 x 2√1 = 2400J√1
(Total 3mks)
(Total 3mks)
M .A
x 100
V .R
3000
= 2.5
1200
20
 4 √1
5
=
2.5
 100 √1
4
=
62.5%√1
(Total 3mks)
- Oiling / greasing the movable parts to reduce friction.
- Use lighter materials for movable parts.
(c)
√√2
Potential Energy
14. (a) - Pressure√1
- Impurities√1
(b) (i) 620C√1
(ii) I.
Q = VIt =
Pt
=
500 x (7.5 – 4.5)60
=
500 x 3 x 60√1= 90,000J√1
II.
Heat supplied by heater =
Heat gained to meet solid X
(Total 2mks)
(Total 2mks)
(Total 2mks)
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232/1,232/2,232/3 physics
(iii) I.
II.
90,000
=
0.6 x Lf
Lf
=
90,000
5
1
√1= 1.5  10 gkg
0.6
Room temperature
At t = 0 = 240
t = 4 min
=
temperature change
MCD  =
Pt√1
C
=
240C√1
=
62 – 24 =
(Total 1mk)
620
380
Pt
500  4.5  60
√1

MD
0.6  38
=
=
5921.05Jkg-1k-1 √1
15. (a) - Nature of surfaces√1
- Normal reactional force. √1
(b) (i)
FA
Kinetic frictional force. √1
I.
FB
Static frictional force. √1
II.
Block slides with stead speed. √1
(ii) Normal reaction =
mg
=
(2x10) =
20N√1
Fr
=
M R
M
(Total 2mks)
(Total 3mks)
(Total 2mks)
(Total 2mks)
(Total 1mk)
Fr 5
√1

R 20
=
0.25√1
=
(Total 3mks)
(c)
U
F
W
U – Upthrust force
F – Viscous drag
W – Weight of steel ball (any 2) (2mks)
16. (a) This is due to constant change in direction of a body hence change in velocity is acceleration.
(b) (i)
w
=
2f  2  3.142  2
I. w
=
v
=
rw
=
0.5x12.567
=
6.283m/s√1
II. h = ½ gt2
But
R = ut√1
20 = 5t2
= 6.283 x 2
t = 2s√1
= 12.566m√1
(ii) I.
T
=
=
=
II. T
=
Mv 2
 mg √1
r
0.04  6.283 2
 0.04  10 √1
0.5
2.758N√1
Mv 2 0.04  6.83 2

√
r
0.5
=
3.7319N√
(c) - In designing and construction of racing tracks for fast moving vehicles. √
- In the construction of a type of speed√ governor in vehicle.
Page | 166
232/1,232/2,232/3 physics
NANDI EAST, NANDI SOUTH & TINDERET SUB-COUNTIES JOINT EXAMS 2016
232/2 – PHYSICS PAPER 2 - MARKING SCHEME
1. Image formation takes place with regular√1 reflection not with diffuse reflection.
Plane mirror – regular reflection.
√1
Sheet of paper – irregular diffuse reflection.
2
2. E  V t
R
240
 240
=
 10  60 √1
120
= 288000
= 2.88 x 105J
3. X-rays, ultraviolet, visible light, radio waves. √1
4.
Total resistance
R1 
RS  R3
+r
R2  R3
63
+0.3
9
=
0.5 
=
2.8 √1
Total current =
=
I
=
E
r
R
6 .6
2 .8
=
2.357A
=
6
 2.357
9
=
1.571A√1
5.
6.
Dry cells uses solid electrolyte while wet cells uses solution of an electrolyte.
7.
226
Ra
88
5
8.
206
4
0
Pb + X He + Y

82
2
1
4x = 226 – 206
-y = 6 – 10
Alpha√1 particles and 4 Beta√1 particles;
4x
4
4
y=4
x =
5
Total capacitance in parallel =
20 + 20 =
X in series with 40  F√1
226 = 206 + 4x + 0
=
20
88 = 82 + 2(x) – y
-y = -4
40  F
1 1 1

 ;
x 40 5
1 1 1
√1
 
x 5 40
8 1 7
=

40
40
1 7

x 40
40
x
 5.71F √1
7
9. Forms a magnified image;
10.
11. - Fuse is on neutral wire, if it blows out, the entire circuit remains live. √
a. Switch S2 is on the neutral wire when off, the rest of the circuit remains live. √1
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232/1,232/2,232/3 physics
b. Two bulbs L3 and L4 are in the series when one goes off, the other goes off also and the voltage is shared.
12. (a)
(b) Wires attracts each other; √1
13. Highly penetrating. √1
14. (a) (i) Transverse waves;
(ii) The particles of medium do not move in direction of waves, they vibrate in their fixed position;
(iii)
f 
=
1
√1
T
1
0.25
=
V
=
0.28
=
  0.07m; √1
4Hz; √1
f
4  √1
(iv)
A
B
Note: Increase in wavelength.
(b) V =
f
=
50,000 x 0.05;
=
2500m/s
Depth
=
2,500 x ½ x 10;
=
12,500m
15. (a) (i)
Dispersion of white light. √
(ii)
X – Red√
Y – Violet√
(iii) Red has the lowest frequency / longest wavelength hence it is least deviated while violet has the highest frequency /
short wavelength hence it is most deviated. √
(iv) Acts as a point source of light. √
(b) (i)
n
n
=
(ii) u
1
sin c
1 √
sin 42;
1.4945
=
=
Speed in air
Speed in glass
Speed in glass
=
3.0  10 8
√
1.4945
16. (a)
(b)
(c)
(d)
8
2.007 x 10 m/s√
=
Real depth
=
30mm√
Apparent depth
20mm
= 1.5√
Production of emf in a coil by changing current in another coil near it.
(i)
Strength of magnet√
(ii)
Number of turns√
(iii)
Winding of a coil soft iron core
(i)
A – Secondary coil
B – Primary coil
C – Capacity
(ii)
It increases the speed of switching on ―break‖ producing higher voltages.
(i)
Power input
=
Power output
80
I = 120 x 12√√
 240
100
=
(c) u
1.5√
Page | 168
232/1,232/2,232/3 physics
I
=
120  12
= 7.5A√
1920
(ii) Eddy currents – Hysteresis loss
Resistance in wires
17. (a) (i)
(ii)
(any two)
14
2.5 x 10 Hz √
1.8  0.2
√ (or any two points correctly read off the graph)
(7.5  3.0) x10 14
h
1.8  0.2 √

e 7.5  3.0 10 14
h
1.6
 1.6  10 19
4
h  6.4  10 34
(iii) Work function = hf0
2.5  1014  6.4  10 34
19
1.6 x 10 J√
c
(b) Wo
=
h
o
hc 6.63  10 34  3  10 8
o 

√
wo
2.4  10 18
18
= 8.2875 x 10 m√
(c)
1cm
Peak voltage – 1mk
Correct period – 1mk
T
1
 0.04s
25
 No. of divisions
0.04  1000
10
= 4 divisions
18. (a) A semiconductor that contains impurities to boost its electrical conductivity.
(b) (i) Half-wave rectification
(ii) During the first half cycle, the diode is forward biased, hence current flows in the second half cycle, the diode is
reverse biased therefore no current flow. In the next cycle, the process repels itself.
(iii)
- Output cycle is not smooth. √
- Power loss at the half-cycle is eliminated. √
(iv)
=
Time in (s)
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232/1,232/2,232/3 physics
1.
Kenya Certificate of Secondary Education
232/2
PHYSICS
Paper 2
2 hours
SECTION A (25MARKS)
Answer all questions from this section.
A positively charged rod is brought close to two spheres A and B, held by insulating handles as shown below.
Indicate the charge on A and B
The sketch below shows the p.d across a cell for various values of current through a resistance wire.
(2 marks)
2.
State and explain the significance of P
The figure below how the displacement of a point varies with time as
(2 marks)
3.
4.
5.

waves passes it.
On the same diagram, draw a wave which passes the point with twice the frequency and half the amplitude of the one shown.
(
2 marks)
A boy standing in front of a cliff blows a whistle and hears the echo after 0.5s. He then moves 17 meters away from the cliff
and blows the whistle again. He now hears the echo after 0.6s. Determine the speed of the sound.
(2 marks)
The figure below shows an object, O, in front of a concave mirror and its image, I, formed after reflection.
a) On the same diagram draw an appropriate ray(s) to locate the principal focus, F, of the mirror.
b) Determine the focal length of the mirror (Scale 1:5)
(2 marks)
(1 mark)
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232/1,232/2,232/3 physics
6.
The figure below shows the image in front of a mirror M.
By ray diagram construction, locate the position of the object.
(2marks)
A negatively charged rod is brought rear the cap of a leaf electroscope. The cap is then earthed momentarily by touching with
the finger. Finally the rod is withdrawn. The electroscope is found to be positively charged. Explain how this is acquired
(2marks)
8. Explain why the e.m.f of a dry cell drops if a large current is drawn for a short time and then recovers if allowed to rest.
(2marks)
9. A heating element rated 2.5 KW is used to raise the temperature of 3.0 kg of water through 50 0C. Calculate the time required
to effect this. (Specific heat capacity of water is 4200 J/kgK)
(3 marks)
10. Other than a photographic film state one other detectors of
i) X-rays
(1 mark)
ii) UV,
(1mark)
iii) Visible spectrum
(1 mark)
11. Give two conditions necessary for formation of annular eclipse.
(2 marks)
SECTION B (55 MKS)
Instruction꞉answer all questions in this section.
12. (a) Define capacitance of a capacitor
(1 mark)
b) The figure below shows a pair of parallel plates of a capacitor connected to a battery. The upper plate is displaced
slightly to the left.
7.
c)
State with reason the effect of this movement on the capacitance.
The figure below shows an electrical circuit with three capacitors A, B and C of capacitance 4.0  F, 5.0
F respectively connected to a 12V battery.
(2 marks)
 F and 3.0 
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232/1,232/2,232/3 physics
Determine:
i) The combined capacitance of the three capacitors.
(3 marks)
ii) The charge on the capacitor C
(2 marks)
iii) The potential difference across the capacitor A.
(2 marks)
13. a)Define refraction of light.
(2 marks)
b) Give one reason for the cause of refraction of light.
(1 mark)
c) The refractive index of glass is 3/2 and that of water is 4/3. Calculate the refractive index of glass with respect to water.
(3 marks)
d) The figure below shows a ray of light incident at an angle of 35.6 0 at point D on the first face of a glass prism ABC. The
refractive index of the prism is 1.6.
i.
Determine the angle of refraction at point D.
Find the angle of incidence of the refracted ray on the face AC.
Complete the diagram to show the emergent ray from the face AC.
14. a) Distinguish between a real and virtual image.
b) An object is placed 15cm from a converging lens of focal length 20cm. calculate the image position.
c) i) Name the eye defect shown in the figure below.
(3marks)
(2marks)
(2marks)
(1marks)
(2marks)
(1mark)
Draw another diagram to show how a suitable lens can be used to correct the defect.
(2marks)
15. (a) State Ohm‘s Law
(1 mark)
(b) The
graph in figure below shows the current –
voltage
characteristics of a certain device, X
(i)
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232/1,232/2,232/3 physics
State with a reason whether the device, X obeys Ohm‘s law.
(ii) Determine the resistance of the device, X, when the current through it is 60mA.
(c) The cell figure has an e.m.f of 2.1 V and negligible internal resistance.
(2 marks)
(2 marks)
Determine the
(i) Total resistance in the circuit
(2 marks)
(ii) Current in the circuit
(1 mark)
(2 marks)
16. An un insulated copper wire XY lies over the fixed wire A and B connected to a battery when the key in the circuit is closed,
the wire XY experiences a force.
(i)
In which direction does the wire XY- experience the force?
(1 mark)
(j) (ii) When is the force on the wire XY greatest?
(1 mark)
(k) (iii) What is the effect of reversing both the magnetic field and direction of flow
of current?
(1 mark)
(iv) State TWO factors by which the force on XY can be decreased
(1 mark)
(vi) Name an instrument which uses this effect
(1 mark)
17. (a) Define diffraction.
(2 marks)
b) In an experiment to observe interference patterns of light waves, a double slit is placed close to the source as shown below.
i)
State the function of the double slit.
(1mark)
Briefly describe what is observed on the screen.
(3 marks)
ii) State and explain what is observed on the screen when the slit separation S1 –S2 is reduced
(2 marks)
iii) State and explain what is observed on the screen when white light is used in place of
the monochromatic light.
(3 marks)
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1.
2.
3.
4.
5.














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233/3
PHYSICS
PAPER 3 - CONFIDENTIAL
INSTRUCTIONS TO SCHOOLS
Question 1
Each student should be provided with the following:Two 100g masses with a hook.
Two strings 30cm long.
A metre rule.
25cm high knife edge.
250ml beaker with salt solution (50g salt dissolved in 200ml of water)
Question 2A
Each student should be provided with the following:Ammeter (0 – 1A)
Voltmeter (0 – 3V)
2 dry cells
A nichrome wire SWG 24 fixed on a metre rule, labelled Y.
A nichrome wire SWG 32 of length 50cm fixed on a piece of wood labeled X.
A switch.
Seven connecting wires 4 with crocodile clips.
A cell holder to accommodate 2 dry cells.
A micrometer screw gauge (To be shared)
Question 2B
Each student should be provided with the following:A crosswire fixed on a screen, labelled screen B.
A candle.
A screen labeled screen A.
A convex lens of focal length, f = 20cm.
A convex mirror of focal length f = 10cm.
Lens holder.
A metre rule.
Mirror holder.
Kenya Certificate of Secondary Education
232/3
PHYSICS
Paper 3
(Practical)
March/April, 2016
2 hours
1. Question one
You are provided with the following:
 Salt solution in a 250ml container
 Two identical cylindrical 100g masses
 A string
 A metre rule
 Knife edge
Procedure
(a) Determine the volume V, of one of the masses by using the apparatus provided. Record the volume, V.
V
=
____________________________________
Explain how you have determined the volume, V.
(i) Determine the centre of gravity of the metre rule
Centre of gravity
=
_______________________
(1mark)
(1mark)
(1mark)
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232/1,232/2,232/3 physics
(ii) Arrange the apparatus as shown in diagram 1 below. Show that the metre rule is at equilibrium, starting with X = 100mm.
Measure and record the length, Y.
Y:____________________________________________
(b) Repeat procedure a (ii) with the following values of X and fill table 1 below.
Table 1
X (mm)
100
150
200
250
300
(1mark)
350
Y(mm)
(i) On the grid provided, plot a graph of Y (y-axis) against X.
(5marks)
(ii) Determine the gradient, N, of the graph.
(3marks)
(iii) The gradient, N, given by the equations N = F/W, where F is the apparent weight of the mass in the salt solution and W is the
actual weight of the mass. Calculate the value F and the up thrust, U.
F = _________________________________________ (1mark)
U =_____________________________________
(2marks)
(iv) Hence determine the density, p of the salt solution.(2marks)
2. Question 2
Part A
You are provided with the following apparatus: Ammeter (0 – 1A)
 Voltmeter (0 – 3V)
 2 dry cells.
 A resistance wire fixed on a metre rule, labeled Y.
 A resistance wire fixed on piece of wood, labeled X.
 A switch.
 Seven connecting wires, 4 with crocodile clips.
 A cell holder, to accommodate two dry cells.
 A micrometer screw gauge (To be shared).
Proceed as follows:
i. Set up the circuit as shown in the diagram 2 below.
Diagram 2
ii.
Keeping both crocodile clip attached on the resistance wire QZ for a length L = 0.2m from Q, record the corresponding values
of current, I (A) and Voltage, (V) in table 2 below.
iii. Repeat procedure (ii) for other lengths, L = 0.4m, 0.6m, 0.8m and 1.0m.
Table 2
Length (L) (m)
0.2
0.4
0.6
0.8
1.0
Current (I) (A)
Voltage (V) (V)
iv. Plot a graph of V (y-axis) against I on the grid provided below
(5marks)
v. Calculate the slope, S of the graph.
(3marks)
vi. Using the micrometer screw gauge provided, measure the diameter, d of the resistance wire labeled X
d = ______________________________________________ m
(1mark)
v. Calculate the quantity, K of the wire from the equation: (2marks)
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232/1,232/2,232/3 physics
K
=
, giving its units. Where S is the gradient in (v) above.
PART B
You are provided with the following: A cross wire fixed on a screen.
 A candle.
 A screen.
 A convex lens.
 A convex mirror.
 A metre rule.
(i) Determine the focal length f1 of the lens by locating the image of a distant object.
f1 = _______________________________________
(1mk)
(ii) Place the lens at a distance of x = 35cm from the crosswire and move the screen A until a sharp image of the crosswire is
focus on it as shown in the diagram 3 (a) below.
Diagram 3(a)
(iii) Without moving the lens and the screen A, place a convex mirror as shown in diagram 3(b) below and move it until a sharp
image of the cross wire is formed on the screen B next to the crosswire.
Diagram 3(b)
(iv) Measure the distance, d between the lens and the mirror and record on table 3 below.
Table 3
Distance, x of lens from crosswire (cm)
Distance, y(cm)
Distance, d(cm)
35
40
y – d (cm)
(3marks)
(v) Repeat procedure (ii) to (iv) for the value of x = 40cm.
(vi) Calculate the mean value of (y – d)
(vii) Calculate the quantity, f2 of the convex mirror from the equation below.
(1mark)
(
)
f2
=
(1mark)
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232/1,232/2,232/3 physics
PHYSICS - MARKING SCHEME
PHYSICS PAPER 2 MARKING SCHEME.
1.
2.
P is the emf of the cell1
Emf is this pd across a voltage source when it is not producing current
3.
Amplitude 
1 Cycle
Frequency 
4.

V=
5.
1
2
d 17  2

 340ms 1  1
2
t
0.1
1
2
(a)
Correct rays with arrows.
F
marked.
(b) 3×5=15
6.
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232/1,232/2,232/3 physics
7.
8.
On earthing negative charges are repelled to the ground. When the rod is withdrawn, the leaf if left with a net positive charge
Manganese (iv )oxide is a slow depolarizer and polarization occurs with a large current, on resting, the depolarization returns
the p.d of the dry cell.Heating makes the depoles to be excited to a high energy state where they
9. p x t = MC ∆ θ
2.5 x 1000t = 3 x 4200 x 50
T= 252s
10. (i) Scintillation tube, Geiger muller tube etc.
(ii) Fluorescent materials, paper smeared with Vaseline etc.
(iii) Eye, photometer.
11. – sun‘s rays fails to reach the earth‘s surface ; due to varying position of the moon.
- moon fails to cover the sun completely because of its smaller size than the sun.
SECTION B.
12 a) capacitance is the measure of charge stored by a capacitor / capacitance c is the charge stored in a capacitor per unit
voltage.
b) Capacitance decreases because area of overlap decreases.
c
i)
Parallel: 5+3=8  f
Whole circuit
C=

8F  4 32

 2.67F
12
12

(ii)
(iii) VC=
charge, Q=CV=
Q 3.2  10 5

 8V
C
4  10 6



8
 12  32 3.2  10 5 c
3



VA=12-8=4V
13a) Refraction is the bending of light as it travels from one medium to another of different optical densities.
b) -change in velocities of light from one medium to another
- change in wavelength of light from one medium to another.
c) wη g=wηa x aηg
= 3/4 x 3/2
= 9/8
d) i) η = Sin i
Sin r
1.6 = Sin 35.60
Sin r
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232/1,232/2,232/3 physics
r = sin
-1
(Sin 35.6)
1.6
= 21.30
ii) Angle of incidence = 38.70 (show working)
iii) sin C = 1 = 1
η 1.6
C = 38.70
14a) Real image is formed when rays of light are brought to a focus/meet while virtual image is formed when rays of light appear
to meet but do not actually meet.
b) 1 = 1 + 1
f
u
v
1= 1+1
20 15 v
V = -60cm
 Image is 60cm from the lens and on same side as the object.
c) i) Long sightedness (hypermetropia)
ii)
15. The ratio of the pd across the ends of a metal conductor to the current passing through it is a constant (conditions must be
given)
(1 mk)
(b) (i) It does not obey Ohm‘s law; because the current — voltage graph is not linear through line origin / directly
proportionate.
(2mks)
v
I
= inverse of slope ; gradient =
1
V
0.74  0.70V
(ii) Resistance =
80  50 mA
0.4V
30  10 3 A
 1.33

(2 mks)
1.20  1.45 (range)
(iii)
From the graph current flowing when pd is 0.70 is 60.MA
Pd across R = 6.0 - 0.7= 5.3v
R = 5.3 V
36mA
= 147  Q
= 139.5— 151. 4 
(c) Parallel circuit
1/30 + 1/20 = 5/60 or 60/50
R= 12 
Total resistance = 10 + 12 = 22 
(3 marks)
V 2.1

 0.095 A
R 22
2.1
(iii) V = I
10
22
(ii) 1 
(2 marks)
(1 mark)
16. i) Towards the right
ii) -When the wire is positioned at right angle to the magnetic field.
-It is minimum when the wire is parallel to the magnetic field.
iii) No effect
iv) - Reducing the amount of current.
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232/1,232/2,232/3 physics
- Replacing the magnet with a bar magnet
- Increased Pressure
- Impurities
b) Specific Latent Heat of vaporization is the quantity of heat required to change 1kg/a unit mass of liquid at 100 0C boiling
point completely to vapour at constant temperature.
c)
(i)
123 – 120 = 3g or 0.003 kg
(ii)
Heat for water
Heat calorimeter
0.070 x 4,200
0.05 x 390
x 25
x 25
= 7,350J
= 487.5J
Total = 487.5 + 7,350 = 7,837.5J
(iii)
I.
ML + MC∆ θ = 7837.5
II.
0.003L + 0.003 x 4200 x 70 = 7837.5
0.003L + 882 = 7837.5
L= 2.3185 x 106
Or
L= 2.32 x 106J/kg
17a) Diffraction is the ability of waves to pass over obstacles.
b).(i) The double slit allows for diffraction of light √ to occur creating an interference pattern on the screen
(ii) Alternating series of dark and bright fringes are observed √
Decreasing in intensity from centre outwards√
The bright fringes are due to constructive interference √
While dark fringes are due to destructive interference.√
(iii) When the slit separation B reduced , the distance between peaks on the interference patter
inteference pattern
increase √
17a)
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PHYSICS - MARKING SCHEME
PAPER 3
1. (a) V = 14ml + 0.1ml1 or 14cm3+ 0.cm3
- Pour some water in the measuring cylinder and record the volume V1.
- Lower the 100g mass into the measuring cylinder using a string and record the new volume VS. ½
Therefore volume of 100g mass = V2 – V1. ½
(1mk)
(b) (i) Centre of gravity = 50cm + 0.51
(1mk)
(ii) X
=
10cm
Y =
9.3cm1 or 930mm
(1mk)
(1mk)
(c)
Xmm
100
150
200
250
300
Ymm
93
133
178
221
263
+1mm ½ each
(d) A GRAPH OF YCM AGAINST XCM
Graph
P – 2, A – 1. S – 1, L – 1 ………………………………………
Xmm
10
15
20
25
30
Ymm
9.3
13.3
17.8
22.1
26.3
NOTE:
S – Scale: simple and uniform.
A – Axes: labeled with correct units.
P – plotting: 4 – 5 points – 2mks
2 – 3 – 1mk
<2 – 0
L – Straight line through the origin.
(e) N
=
DY
=
18.5 – 12
=
6.5
DX
21 – 13.5
7.5
=
0.86671 (unit less)
(f) Given N
=
F/W
where F – apparent weight of mass in salt solution.
W – actual weight of mass in air.
(g) F =
WN but w = 0.1kg x 10N/Kg = 1N
=
0.8667 x 1
=
0.8667N = 0.87N1
(ii) U
=
W–F
=
(1 – 0.8667) 1
=
0.133
~
0.13N1
350
306
(5mks)
35
30.6
(3mks)
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232/1,232/2,232/3 physics
(h) Upthrust
0.13
p
=
2.
(iii) Table
(iv)
=
pvg
=
p x 14 x 10-6 x 10
=
0.131
14x10-6 x 10
928.57Kg/m31
Length (L) (m)
0.2
Current (I) (A)
0.22
Voltage (V) (V)
1.60
5 values – 4mks
4 values – 3mks
3 values – 2mks
2 values – 1mk
0.4
0.20
1.50
0.6
0.19
1.40
0.8
0.17
1.30
1.0
0.16
1.20
NOTE:
S – Scale: simple and uniform.
A – Axes: labeled with correct units.
P – plotting: 4 – 5 points – 2mks
2 – 3 – 1mk
<2 – 0
L – Straight line through the origin.
=
Points on the line – 1mk1
Substitution
=
7.43575 +2Ω (1mk) 1
(vi) d = 0.21 + 0.01mm =
2.1 + x10-4m 1mk1
(vii) K
= 7.43575 x (2.1E – 4)2 x π =
5.15 x 10-7Ωm
Substitution – 1mk 2
Part B
(i) f1 =
20.0 + 2.0cm
(1mk)
(iv)
Distance, x of lens from crosswire
Distance, y(cm)
Distance, d(cm)
(cm)
+1cm
+1cm
35
19.0½
52.5½
45
11.0½
43.0½
( ½mk each, 1 mk both)
(v) (33.5 + 32) / 2
=
32.75cm1
(1mk)
(vii) f2 =
32.75 =
16.75cm1
(1mk)
2
+0.05A2
+0.2V2
y – d (cm)
33.5½
32½
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232/1,232/2,232/3 physics
GATUNDU SOUTH FORM FOUR JOINED EVALUATION EXAM
Kenya Certificate Of Secondary Education
1.
2.
3.
232/1
PHYSICS
PAPER 1
JULY/AUGUST 2016
TIME: 2 HOURS
SECTION A (25 MARKS)
The figure below shows a spherical ball placed between 2 wooden blocks and a metre rule.
What is the volume of the ball?
(3 Mks)
A solid weighs 16.5N on the surface of the moon. The force of gravity on the moon is 1.7N/kg. Determine the mass of the
solid.
(2 Mks)
The figure below shows two cylinders containing a liquid and connected with a tight – fitting flexible tube. The cylinders are
fitted with air – tight pistons A and B as shown.
When equal forces, F are on the pistons as shown, what is observed. Explain the observation.
(3 Mks)
4. A bottle of soda stands on a bench. As the temperature of the surrounding rises the temperature of the bottle also rises. State
and explain the effect of this on the stability of the bottle.
(3 Mks)
5. Explain how heat loss by ;
(1 Mk
(ii) Conduction is minimized in a vacuum flask.
(1 Mk)
6. The figure below shows part of the main scale of vernier valipers.
Insert the vernier scale to the main scale, to show a reading of 3.62 C.M
(1 Mk)
7. A liquid flows into a pipe of varying cross sectional area. The inlet cross section is 10cm in diameter. If the liquid leaves the
pipe at 0.5m3/s find the inlet velocity of the liquid.
(3 Mks)
8. The three springs shown below are identical and have negligible weight. The extension produced on the system of springs is
20cm.
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232/1,232/2,232/3 physics
9.
Determine the constant of each spring.
(2 Mks)
The figure below shows a uniform metre rule of weight 1N with two weights 0.18N and 0.12N suspended from its ends.
0
100cm
0.18N
0.12N
Determine how far from the 0.18N weight a pivot should be placed in order to balance the metre rule.
(3 Mks)
10. An athlete runs at 4m/s from point A to point B and immediately turns and runs back from B to A with a speed of 8m/s.
Calculate the average speed of the athlete.
(3 Mks)
SECTION B: 55 MARKS.
11. (a) In a car, the engine drives an alternator which produces electricity that lights the headlights. List the energy changes
involved.
(3 Mks)
(b) What is the power output of a pump which can raise 60kg of water to a height of 10m every minute.
(3 Mks)
(c) If the efficiency of the pump in 11(b) is 80%, how much power must be supplied (2 Mks)
12. (a) A mass, 5kg moving with a velocity of 10m/s collides with a 10kg mass moving with a velocity of 4m/s in the same
direction along the same line. After collision, the 5kg mass moves with a velocity of 7.0m/s. Calculate the velocity of the
10kg mass.
(3 Mks)
(b) Explain why a steel ball falling through oil, will first accelerate after which the acceleration falls to zero.
(3 Mks)
13. (a) State one factor that affects the rate of evaporation. (1 Mk)
(b) A thin wire is passed round a large block of ice and two heavy weights are attached to the ends. It is observed that the wire
passes through and the ice remains as a single block.
Explain the observation.
(2 Mks)
(c) The graph below shows the cooling curve of naphthalene.
State what is happening at points;
(i) A – B.
(1 Mk)
(ii) B –C.
(1 Mk)
(d) A copper calorimeter of mass 50g contains 80g of oil at 25oC.A piece of ice of mass 25g at 10oC is added to the oil. What
mass of ice will be left when the temperature of the calorimeter and its contents will be 0 oC.
(6 Mks)
14. (a) An air bubble of volume 0.5cm3 when released from the bottom of a lake rises to the surface of the lake.
(i) Explain why the bubble rises up.
(2 Mks)
(ii) Calculate the volume of the bubble at the surface of the lake given that the lake is 92.7m deep and the atmospheric
pressure is equivalent to 10.3m of water pressure.
(4 Mks)
(1 Mk)
(b) A fixed mass of gas at constant pressure has a volume of 600cm3 at 0oC. At what temperature will its volume be 1099
cm3.
(3 Mks)
15. (a) (i) Define centripetal force.
(1 Mk)
(ii) Explain why no work is done by a centripetal force acting on a body moving in a horizontal plane.
(1 Mk)
(iii) A body of mass m is tied to a string in a vertical plane with a constant speed V. Tensions in the string at positions A,
B and C marked TA, TB and TC respectively.Arrange the tensions TA, TB and TC in ascending order. (1 Mk)
(iv)
Explain why wet clothes put in a spin dryer, drys faster when the spin drum is rotated at a higher speed.
(2 Mks)
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(b) A particle revolves at a frequency of 5 H3 in a horizontal circle of radius 2m.
Determine its;
(i) angular velocity.
(2 Mks)
(ii) Linear velocity.
(2 Mks)
(iii)
Centripetal acceleration.
(2 Mks)
16. The figure below shows a metal sphere of mass 400kg and volume 0.6m3 fully submerged in sea water of density 1030kg/m3
Determine;
(a) The tension in the cable holding the sphere.
(4 Mks)
(b) The radius of the sphere.
(2 Mks)
(c) The weight of a solid in air is 5N. When it is fully immersed in a liquid of density 800kg/m 3 its weight is 4.04N.
Determine;
(i) The upthrust of the liquid.
(1 Mk)
(ii) The volume of the solid.
(2 Mks)
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GATUNDU EVALUATION EXAMS 2016
1.
2.
Kenya Certificate Of Secondary Education
PHYSICS PAPER 2 (232/2)
TIME 2 HOURS
SECTION A: 25 MARKS.
Answer all questions in this section in the spaces provided.
Give a reason why it is necessary to leave the caps of the cells open when charging an accumulator.
The figure shows a ray of light incident on a face of semi-circular glass block.
(1 Mk)
Glass
block
3.
4.
5.
Determine the angle of incidence (refractive index of glass = 1.5)
(2 Mks)
Explain how doping produces a p-type semiconductor from a pure – semi conductor material.
(2 Mks)
When a highly positively charged rod is gradually brought towards a negatively charged electroscope. It is observed that the
leaf divergence first decreases and then increases when the rod moves near to the cap. Explain
(2 Mks)
Calculate the effective capacitance of the capacitors shown in the figure below.
(2 Mks)
60μF
30 μF
20µF
6.
7.
8.
State how the deflection system of a television differs from that of a C.R.O
(2 Mks)
State two factors affecting the type of shadow formed by a fixed size object placed in front of a source of light. (2 Mks)
The wave shown in the figure below has a speed of 100m/s. Study and answer question below.
1
Displacement (cm)
0.5
0
50
100
150
200
250
300
350
400
X 10 -4 s
-0.5
-1
Calculate the wavelength of the wave. (3 Mks)
Explain In terms of domain theory what happens when a bar magnet is placed in a solenoid in which an alternating current
flows.
(2 Mks)
10. If the half life of a radio active gas is 2 minutes, then after 8 minutes the activity will have fallen to afraction of its initial
value. Determine this fraction.
(2 Mks)
9.
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11. In each case, the pattern of the waves is incident on the slit and the emergent pattern is shown.
Diagram 1
diagram 2
Which action would cause the waves in diagram 1 to be diffracted less and so produce an emergent pattern closer to that
shown in diagram 2.
(1 Mk)
12. Explain why the cathode of a cathode ray tube is coated with oxides of metals such as strontium and barium.
(1 Mk)
13. State why optical fibers are preferred in communication to ordinary cables. (1 Mk)
14. A student was investigating the brightness of bulbs with set up in circuits. He used identical bulbs and cells. The circuits A
and R were set up as shown.
State and explain which set-up had the bulbs brightest. (2 Mks)
SECTION B - 55 MARKS.
15. (a) The figure below shows a photocell P in action
MA
R
Ultraviolet
light.
photocell
(i) Give a reason why the photocell is evacuated. (1 Mk)
(ii) What is the function of the resistor R in the circuit? (1 Mk)
(b) The following graph was plotted for the results obtained from an experiment on photoelectric effect. Given that eVs =
hfo– Wo where h is planks Constant and Wo is the work function of the metal used. Use the graph to:
(i) Determine the threshold frequency.
(1 Mk)
(ii) The plank‘s constant.
(4 Mks)
(iii) The work function for the metal. (take charge of an electron e = 1.6 x 10 -19 J)
(2 Mks)
(c) (i) Sodium has a work function of 2.0eV.
Calculate the least frequency of radiation by which electrons are emitted.Use the value of h obtained from the graph above.
(3 Mks)
16. (a) State the Lenz‘s law of electromagnetic induction.
(1 Mk)
(b) List three features in a transformer which improves its efficiency.
(3 Mks)
(c) A step down transformer has 800 turns in the primary coil and 40 turns in the secondary coil.
A 100Ω resistor is connected to the secondary output. If the primary voltage is 240V, calculate;
(i) The output voltage.
(3 Mks)
(iii) The secondary current.
(3 Mks)
17. (a) An object is placed 30cm in front of a thin converging lens of focal length 20cm. The set up is represented in the figure.
lens
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232/1,232/2,232/3 physics
(i) On the same figure construct a ray diagram to locate the position of the image.
(ii) Determine the magnification produced.
(b) An object 6cm tall is placed 40cm from a convex lens of focal length 50cm.
Find the position of the image. (2Mks)
(c) State two differences between the human eye and the camera.
(d) The figure below shows an eye defect.
(3 Mks)
(2 Mks)
(2 Mks)
(i) Identify the defect.
(ii) State the cause of the defect.
18. (a) (i) Define background radiation.
(ii) State two sources of background radiation.
(b) State two differences between alpha and beta particles.
(c) State one use of radioactivity in each of the following areas.
(i) Agriculture.
(ii) Medicine
[
(1 Mk)
(1 Mk)
(1 Mk)
(2 Mks)
(2 Mks)
(1 Mk)
(1 Mk)
]
[
(d) Uranium
Find the number of alpha and beta particles emitted in the process. (3 Mks)
19. (a) The circuit diagram in the figure below shows three identical resistors connected to a cell of e.m.f 12V
P
Q
R
]
V
R
R
T
S
(i) Determine the reading of the voltmeter.
(ii) If another identical resistor R is connected parallel to PT, determine the potential difference across Qs.
(b) Explain why the earth pin in the mains plug is longer than the neutral and live pins.
(c) Give one example of a semi conductor and one example of a conductor.
(d) A hair dryer rated 1000W, 240V runs for 3 hours per day for 7 days. Calculate;
(i)The number of KWh used.
(ii)The cost of electricity paid at the rate of Ksh 5.50 per unit.
(2 Mks)
(3 Mks)
(1 Mk)
(2 Mks)
(2 Mks)
(2 Mks)
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PHYSICS - MARKING SCHEME
PAPER 3
1. (a) V = 14ml + 0.1ml1 or 14cm3+ 0.cm3
(1mk)
- Pour some water in the measuring cylinder and record the volume V1.
- Lower the 100g mass into the measuring cylinder using a string and record the new volume VS. ½
Therefore volume of 100g mass = V2 – V1. ½
(1mk)
(b) (i) Centre of gravity = 50cm + 0.51
(1mk)
(ii)
X =
10cm
Y =
9.3cm1 or 930mm
(1mk)
(c)
Xmm
Ymm
100
93
150
133
200
178
250
221
300
263
+1mm ½ each
(d) A GRAPH OF YCM AGAINST XCM
Graph P – 2, A – 1. S – 1, L – 1 ………………………………………
Xmm
10
15
20
25
Ymm
9.3
13.3
17.8
22.1
30
26.3
NOTE:
S – Scale: simple and uniform.
A – Axes: labeled with correct units.
P – plotting: 4 – 5 points – 2mks
2 – 3 – 1mk
<2 – 0
L – Straight line through the origin.
(e) N = DY =
18.5 – 12
=
6.5
DX
21 – 13.5
7.5
= 0.86671 (unit less)
(f) Given N = F/W where F – apparent weight of mass in salt solution.
W – actual weight of mass in air.
(g) F = WN but w = 0.1kg x 10N/Kg = 1N
= 0.8667 x 1
= 0.8667N = 0.87N1
(ii) U = W – F
= (1 – 0.8667) 1
350
306
(5mks)
35
30.6
(3mks)
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=
~
(h) Upthrust
0.13
p
0.133
0.13N1
=
pvg
=
p x 14 x 10-6 x 10
=
0.131
14x10-6 x 10
=
928.57Kg/m31
2.
(iii) Table
Length (L) (m)
Current (I) (A)
Voltage (V) (V)
5 values – 4mks
4 values – 3mks
3 values – 2mks
2 values – 1mk
(iv)
0.2
0.22
1.60
0.4
0.20
1.50
(vi)
NOTE:
S – Scale: simple and uniform.
A – Axes: labeled with correct units.
P – plotting:
4 – 5 points – 2mks
2 – 3 – 1mk
<2 – 0
L – Straight line through the origin.
=
Points on the line – 1mk1
Substitution
= 7.43575 +2Ω (1mk) 1
d = 0.21 + 0.01mm
=
2.1 + x10-4m 1mk1
(vii)
K
(v)
=
7.43575 x (2.1E – 4)2 x π =
2
Part B
(i) f1 = 20.0 + 2.0cm
0.6
0.19
1.40
5.15 x 10-7Ωm
0.8
0.17
1.30
1.0
0.16
1.20
+0.05A2
+0.2V2
Substitution – 1mk
(1mk)
(iv)
Distance, x of lens from crosswire
(cm)
35
45
(v) (33.5 + 32) / 2
(vii) f2 = 32.75
2
=
=
32.75cm1
16.75cm1
Distance, y(cm)
+1cm
19.0½
11.0½
Distance, d(cm)
+1cm
52.5½
43.0½
y – d (cm)
33.5½
32½
( ½mk each, 1 mk both)
(1mk)
(1mk)
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KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
TIME: 2 HOURS
JULY/AUGUST, 2016
1. In the space below give a sketch of a closed micrometer screw gauge showing an error of +0.02.
(1mk)
2. The figure 1 below shows a measuring cylinder which contains water initially at level A. When a solid of weight 0.3N was
immersed in the water, level rose to B.
Fig. 1
Use this information to answer the question that follow.
Determine the density of the solid mass giving your answer in g/cm3.
3. The figure 2 below shows a match stick floating on the surface of water in a basin,
4.
5.
(3mks)
Fig. 2
When a drop of soap solution was carefully added to the water at A, the match stick is observed to move in a certain
direction. State the direction of this match using A and B and explain this observation.
(2mks)
The figure 3 below shows a cube of a certain wood whose density is the same as the density of water held on the surface of
water in a beaker. Complete the figure (b) to show the final position of the cube when it is released.
(1mk)
Fig. 3
(a)
(b)
A block of metal of mass 5 kg is heated to 1100 and then gently immersed in 2kg of water in a container of negligible heat
capacity. The final temperature of water is found to be 50 0C. What was the initial temperature of the water?
Specific heat capacity of metal = 840jKg-1K-1
Specific heat capacity of water = 4200jKg-1K-1
6.
7.
8.
9.
(3mks)
A spring of spring constant 60n/m is extended through 50cm. Calculate the amount of work down in stretching.
(2mks)
Explain why it is sometimes easier to remove a metallic lid from a tightly closed glass jar after warming it under hot running
water.
(2mks)
Heat transfer by radiation is faster than heat transfer by conduction. Explain.
(2mks)
The figure 4 below shows a spring full of water. It has two identical holes A and B - drilled along its cylinder. The cylinder’s
nozzle is closed.
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State with a reason how the speed of the jets of water from A and B compared when the piston is pushed into the cylinder.
(2mks)
10. If you are a weatherman stationed in the arctic region (at the earth poles) state with a reason the thermometric liquid most
(2mks)
11. In the figure 5 below distance AC = kB, calculate the force F that will keep the system in equilibrium.
(2mks)
12. The figure 6 below shows parts A, B and C of a glass tube.
Fig. 6
State with a reason the part of the tube in which the pressure will be lowest when air is blown through the tube from A
towards C.
(1mk)
13. The figure 7 below shows a velocity-time graph of a moving body.
Describe the motion of the body over
i) region DE
(1mk)
ii) region EF
(1mk)
14. (a) A bullet of mass 20g moving with a velocity of 100m/s embed on a stationery object of mass 900g suspended so that it
can swing freely as shown in the figure below.
Determine
i) the velocity of the bullet and block immediately after collision.
(3mks)
ii) the height through which the block rises.
(3mks)
(b) A train travelling at 100km/h increases its velocity to 132km/h in 8 minutes. Calculate its acceleration in m/s. (3mks)
15. (a) The figures below shows a student of mass 60kg sliding freely down the slope AB. She continues and stops at point C.
Fig. 8
The frictional force is one-third of the students weight and acts uniformly all along the slide A to C. Take g = 10m/s 2.
(i) How much potential energy is lost by the student in sliding from A to B.
(2mks)
(ii) Calculate the horizontal distance BC.
(3mks)
(iii) Ignoring friction along AB and air resistance find the maximum velocity with which the student slides at any one
point along the path.
(2mks)
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(b) The figure 9 shows a set of gears used to lift a load attached to the axle P by applying an effort to the axle.
16.
(i) In order to lift the load through a distance of 2m, the axle P must rotate 5 times. How many times must axle Q be
rotated.
(2mks)
(ii) Through what distance must the effort be applied of the axles P and Q have the same diameter.
(2mks)
(a) State the difference between the Archimedes principle and the law of floatation.
(2mks)
(b) The figure below shows three stages of an experiment to determine relative density of a cork, which normally floats on
water.
In (I) above a spring balance is used to measure weight W of the cork in air in (II) the spring balance is used to measure
the apparent weight W1 when only the sinker is submerged in water.
In (III) the spring balance is used to measure the apparent weight W2 when both the cork and the sinker are submerged.
W = 0.0N
W1 = 0.6N
W2 = 0.28N
Use this information to determine the:
(i) upthrust on cork.
(2mks)
(ii) relative density of cork.
(3mks)
(c) The figure below shows two glass tubes of different diameters dipped in water.
Explain why h2 is greater than h1.
(3mks)
d) Some cotton wool soaked in conc. ammonia solution and hydrochloric acid were placed at the ends of a glass tube as
show below.
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After sometime a white deposit of ammonium chloride forms on the walls of the glass tube. Use a mark to show where
the white deposit is formed.
(1mk)
17. (a) Distinguish between streamline and turbulent flow.
(2mks)
(b) The figure below shows two light sheets of paper arranged as shown.
Explain the observation made when air is blown at the same speed and time at point A and B.
(2mks)
(c) The figure below shows an incompressible fluid moving through a tube of varied cross section area. If the area of the small
tube is 0.05m2, Calculate the diameter of the large tube in cm.
(3mks)
(d) Use the figure below to answer the questions that follow.
(i) What is the pressure resting on point A?
(1mk)
(ii) What is the value of pressure difference in the instrument reading?
(1mk)
(iii) If the atmosphere pressure is 760mm of mercury, what is the value of gas pressure?
(2mks)
18. (a) State the factors affecting centripetal force.
(3mks)
(b) A mass of 0.4 kg is rotated by a string at a constant speed V in a vertical circle of radius 1 m.
The minimum tension in the string is 6N.
(i) Indicate on the diagram below the position of the object for the minimum tension,
(1mk)
(ii) Write an expression for this uniform force experienced.
(1mk)
(iii) Use your expression to determine the velocity V.
(3mks)
(iv) Determine maximum tension on the string.
(2mks)
c) Using the kinetic theory of gases explain how a rise in temperature of a gas causes arise in the volume of the gas if the
pressure is kept constant.
(3mks)
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1.
KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
TIME: 2 HOURS
JULY/AUGUST, 2016
Figure 1 below shows an object in front of plane mirror.
Figure 1
Sketch image of object using mirror shown.
2. Figure 2 below shows an object infront of concave mirror and it’s image.
Figure 2
Locate position of its principal focus.
3. State the energy transformations when fast moving electrons are suddenly stopped by metal target.
4. Define the term threshold wavelength as used in photoelectric emission.
5. State the use of Manganese (IV) oxide in dry cell.
6. Use figure 3 below to answer following questions.
Figure 3
Determine
(a) Total resistance.
(b) Potential difference across 4 resistor.
7. Figure 4 shows conductor carrying current in magnetic field and moves in direction shown.
Figure 4
Identify polarities X and Y.
8. Define half life as used in radioactivity.
9. Use figure 5 to answer following question.
(1mk)
(2mks)
(1mk)
(1mk)
(1mk)
(3mks)
(3mks)
(2mks)
(1mk)
Figure 5
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10.
11.
12.
Determine the frequency of wave.
(3mks)
Sketch diode circuit in reverse biased mode.
(1mk)
A student shouts and hears an echo after 0.6 seconds. If the velocity of sound is 330m/s. Calculate the distance between
student and reflecting surface.
(3mks)
Figure 6 shows water waves moving towards barrier.
Figure 6
13. State two properties of cathode rays.
(2mks)
14. (a) State two factors that determine the magnitude of an induced emf in a conductor.
(2mks)
(b) A power station has input of 50kw at p.d. of 10 Kv. A transformer with secondary coils of 1000 turns is used to step
down the voltage to 1000v for transmission along grid. Assuming there is no power loss, calculate:
(i) Current in primary coil.
(2mks)
(ii) Number of turns in primary coil.
(2mks)
(iii) Current in secondary coil.
(2mks)
(c) State which of coils in thicker and why.
(2mks)
15. (a) Define refractive index.
(1mk)
0
(b) The critical angle of a material is 43.2 . Determine the refractive index of that material.
(2mks)
(c) Define the term accommodation as used in lenses.
(1mk)
(d) Figure 7 shows eye deflect
Figure 7
(i) Identify the defect.
(ii) Show how the defect can be corrected on same diagram.
(e) An object is placed 40cm in front of concave lense of focal length 20cm. Determine the position
of the image.
16. (a) Define photoelectron.
(b) State two factors affecting photoelectric effect.
(c) Figure 8 on graph paper shows graph of stopping potential against frequency (graph paper)
(i) Define stopping potential.
(ii) Given that stopping potential (Vs) is related to frequency by equation.
Vs = hf – Wo
e
e
where e = 1.6 x 10 -19 C
Determine from graph
i) Planck’s constant (h)
(1mk)
(2mks)
(3mks)
(1mk)
(2mks)
(1mk)
(4mks)
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232/1,232/2,232/3 physics
17.
(ii) Work function (wo) in (ev)
b) Identify the radiations of tracks in figure 9 below.
Figure 9
(3mks)
(1mk)
(1mk)
(i)
(ii)
(c) Identify radiations using figure 10 below.
(1mk)
(3mks)
Figure 10
X Y and Z
(d) The following reaction is part of radioactive series
Identify radiation h and values of b and c
18. Figure 11 shows cathode ray oscilloscope (CRO)
(3mks)
Figure 11
(a) Name parts labelled A and B
(2mks)
(b) What are the functions of parts labelled C and D?
(2mks)
(c) Why is the tube evaluated?
(1mk)
(d) Four 40w bulbs and six 100w bulbs were switched on for 5 hours a day for domestic use in an institution. Find the
monthly bill for 30 days at rate of sh 5.50 per unit with standing charge of
sh 150.
(3mks)
(e) Figure 12 shows X-ray tube
Figure 12
(i) Identify parts A and B.
(ii) Calculate the number of electrons hitting the anode per second.
(iii) X-ray tube is operating at 15kV and current of 15mA. Determine the velocity of electrons as they
strike the target. (e = 1.6 x 10-19, Me = 9.1 x 10-13 kg)
(2mks)
(2mks)
(3mks)
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232/1,232/2,232/3 physics
KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3
CONFIDENTIAL
Each student should have the following apparatus.
Q1. One stand, two bosses, tow clamps
 Two pieces of thread (10cm)
 A stop watch
 One metre rule
 Two identical springs
 Six 100g masses
 One optical pin
 A piece of cellotape
Q2. Triangular prism of 600.
 Four optical pins
 A softboard
 A plain paper
KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 3 (PRACTICAL)
TIME: 2 HOURS
JULY/AUGUST, 2016
QUESTION 1
1. You are provided with the following
 One stand, two bosses, two clamps
 A stopwatch
 One metre rule
 Two identical springs
 Six 100g masses
 One optical pin
 A piece of cellotape
(a) Tie the two springs together side by side and set up the apparatus as shown.
(i) Hang the springs from rod (of one clamp) as shown in the figure
(ii)Tie together the upper end and the lower ends of the springs with pieces of thread as shown in the figure.
(iii) Hang a 100g mass from the lower ends of the springs so that the mass is supported by both springs.
(iv) Clamp the metre rule vertically.
(v) Use cellotape to fix the optical join on the top of the 100g mass so that it acts as a pointer.
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232/1,232/2,232/3 physics
(vi) Adjust the rule so that the pointer is directly along a particular scale mark of the rule. Record
this mark in the table.
b) i) Add a 100g mass to the first mass. Record the new position of the pointer and the extension, e, in the table.
ii) Add another 100g mass and record the new position of the pointer and the extension in the table.
(iii) Repeat b (ii) until the total mass supported by the spring is 600g.
c) (i) Re move the rule, displace the 600g mass slightly downwards and release it to oscillate vertically.
ii) Time 20 oscillations. Record in the table the time t1 for 20 oscillations. Repeat to obtain the time t2.
Calculate and record the average time and the periodic time T.
(iii) Repeat c(i) and (ii) for 500g, 400g, 300g and 200g masses.
(iv) Find T2 and complete the table.
(9 mks)
d) i) Plot a graph of T2 against extension e
ii) Determine the gradient of the graph and state its units.
iii) The equation of the graph is given by
T2 = 4e + c
b
where b and c are constants. Determine the value of b.
Question 2
You are provided with the following
 A triangular prism of 600.
 Four optical pins
 A soft board
 A plain piece of paper
Proceed as follows
(a) Place the plain sheet of paper on the soft board
(b) Place the prism with one face on the plain paper and trace its outline.
(c) Remove the prism from the plain sheet of paper.
(5mks)
(3mks)
(3mks)
(d) Mark angle A and record its value.
A = .......................... (1mk)
(e) Draw a normal as shown and draw a ray of incident on the normal at an angle of incidence of 30 0.
(f) Replace the prism on the outline on the sheet.
(g) Stick two pins P1 and P2 along the path of the incident ray as shown in the diagram.
(h) View the images of P1 and P2 through the glass prism through face AC as shown on the diagram.
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232/1,232/2,232/3 physics
(i) Stick two pins P3 and P4 so that they appear to be in line with P1 and P2 as seen through the glass
prism.
(j) Remove the pins and prism from the sheet. Trace the path of the ray until it emerges from the
glass as shown in the diagram.
(k) Extend the incident ray and the emergent ray until they meet at P. Measure and record the angle
of deviation d.
(l) Repeat the experiment for other angles of incidence shown in the table.
(8 marks)
(m)
(n)
(p)
Plot a graph of angle of deviation (d)0 against angle of incidence (i)0.
From the graph determine the minimum angle of deviation D.
Find the refractive index of the prism material using
(5 marks)
(2 marks)
(4 marks)
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232/1,232/2,232/3 physics
KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
MARKING SCHEME
1.
2.
3.
4.
5.
f= m=
= 2.5g/cm3
Surface tension at A reduces and greater surface tension at B pulls the matchstick in the direction shown.
Top level must be the same as water level.
Heat lost = Heat gained
5kh x 840JKg-1K-1 (110 - 50)0C = 2 kg x 4200JKg-1K-1 ( 500 - )
 = 200C
6. Work done = 1/2Kx2 = 1/2 x 60N/M (0.5)2= 7.5j
7. Due to the unequal expansion between the metallic lid and glass. Metal expands more than glass for same temperature range.
8. Radiation is an electromagnetic wave while conduction involves particles which vibrate at lower speeds.
9. The speed is the same pressure is transmitted equally to all parts of the cylinder.
10. Alcohol - has a lower freezing point.
11. 150N x AC = F x 2AC
150 x AC = F
2AC
==> F = 75N
12. B - Velocity is highest - pressure lowest
13. i) DE – Body at rest
EF - Body accelerates in the opposite direction.
14. a) i) MbUb = MoUo = MbVo + MoVo
20 x 100 + 90 x 0 = 20 V + 900V
1000
1000
1000 1000
2 + 0 = V ( 0.02 + 0.9)
V = 2 = 2.174m/s
92
(ii) KE = PE
1/ mv2 =Mgh
2
h = V2 = 2.174 = 0.24m
2g 2 x 10
(b) Change in velocity
(132 - 100)km/h = 32km/h
32 x 1000 = 8.89 m/s
60 x 60
Acc = Change in velocity
time taken
= 8.89 = 0.019m/s
8 x 60
15. a) i) g.p.e = Mgh
= 60kg x 10m/s2 x 3= 1800J
ii) Frictional force
1/ x 600 = 200N
3
Work done = F x d= 200 x d
1800 = 200d
1800 = d
200
d = 9m
Since AB = 7m, BC = 2m
iii) Max P.E. lost = Max K.E. gained
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1800J = 1/2 mv2 ==> V2 = 3600
600
V= √
= 7.75m/s
b) i) Percentage ratio of the work done on the load to work done by effort or
MA x 100
VR
ii) Energy lost to overcome friction of moving part
- Lifting parts of the machine.
15. a) i) 3 x 5 = 15 times
ii) 2 x 3 = 6m
16. a) Archimedes principle talks about the relationship between an immersed or partially immersed object and the upthrust on it.
Floatation talks about floating bodies only/partially immersed.
b) i) 0.6 - 0.28 = 0.32N
ii) 0.08 = 8 1 = 0.25
0.32 32 4
c) Surface tension/Adhesive forces support water column or more capillarity in tube 2 than tube 1.
- Surface tension is the same in both tubes and equal to the weight of water column supported.
- Narrow tube has larger column to equate weigh to wider tube
- Volume of water in the bues same hence narrower tube column is higher
d)
17. (a) Streamline flow where all the particles of the fluid move in the same direction at the same velocity at a particular point.
- Turbulent - particles move with different velocities.
(b) Higher air speed at A and B reduces air pressure at A and B. - Higher atmospheric pressure between X and Y pushes paper
outwards.
(c) A1V1 = A2V2
0.05 x 2.6 = 0.1x A2
A2 = 0.05 x 2.6 = 1.3m2
0.1
= 13000cm2
Using r2 = A
r2 = 13000
r2 = 13000
r2 = 13000 ==> r2 = 4137
3.14
d=rx2
= √413 x 2 = 128.65cm
d) i) Gas pressure
ii) 56mm Hg
iii) 760mmHg + 56mmHg = 816mmHg
18. (a) - Mass of the body
- Angular velocity
(b) (i)
(ii) Fmin = MV2 – Mg
r
2
(iii) MV = Fmin + Mg
r
2
0.4r = 6N + 4N ==> V2 = 25
V = 5m/s
iv) Fmax = MV2 + Mg ==> 0.4 x 52 + 0.4 x 10
r
1
= 14N
c) - Rise in temperature give gas molecules more K.E.
- Collisions between molecules increase
- Molecules move further apart in all directions.
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KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
MARKING SCHEME
1.
2.
rays with arrows position of F
3. Kinetic energy ---> Heat + X-rays
4. Maximum wavelength beyond which photoelectric effect does not occur.
5. Depolarizer
 (a) 4 + 3 = 7




(b) I = 12 + 12 = 144 = 4.1143A
35
35
5
C(4 ) = /12 x 4.1143 x 4 = 6.857V
7. X - North
Y - South
8.
Time taken for half mass of given radioactive to decay
9.
T = 0.0025 = 0.000625 s
4
f = 1/T = 1600Hz
10.
11.
S = vt = 330 x 0.6 = 99m
2
2
12.
13. - Travel in straight line
- Charged
- Deflected by magnetic & electric fields any 2
14. a) - Strength of magnetic field
- Rate of change of magnetic flux linkage any 2
- Angle of inclination
- Number of turns in coil
b) i) P = VI
I = 50 000 = 5A
10 000
ii) Ns = Vs
Np = 1000 x 10 000 = 10 000 turns
Np Vp
1000
iii) Vs = Ip
Vp
Is
1s = 10,000 x 5 = 50A
1000
c) Primary coil to minimize resistance
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15. a) Ration of sine of angle of incidence to sine of angle of refraction for a given pair of media.
b)
n
=
1
=
1
Sin C
Sin C 43.20
= 1.461
c) Adjustment of focal length of eye lens so as to focus images of objects of different distances on retina.
d)
Use convex lens to correct
i) Long sightedness (Hypermetropia)
e) 1 = -1 – 1 = -1 – 2 = -3
V
40 20
40 40
V = -13.33cm
16. a) Electrons dislodged due to radiation (photo)
b) - Intensity of incident radiation
any 2
- Type of metal
c) i) Work done on stopping electrons from leaving cathode.
3–0
= 4.0 x 10-15
(12 - 4.5) x 10+14
.: h = 4.0 x 10 - 15 x 1.6 x 10-19 = 6.4 x 10-34js
Wo = y Intercept .: Wo = y - Intercept x e
e
or w = hfo = 6.4 x 10-34 x 4.5 x 1014 = 2.88 x 10-19J
1.8ev
17. a) Distintegration of unstable nucleus
b) i) Beta () particles
ii) Alpha ( ) particles
c) X - alpha ( ) particles
Y - Gamma rays
Z - Beta () particles
d) H - Beta ( ) particles
b - 82
c - 206
18. a) A - Grid
B - Anode
b) C - Vertically deflect the beam
D - Horizontally defect the beam
c) Reduce collision with air molecules in the tube.
d) ( ( 4 x 40) + (6 x 100))5 = 3.8kwh per day
1000
380 x 30 = 114 kwh per minute
Cost (114 x 5.5) + 150 = sh 777
e) i) A - Cathode
B - Anode
ii) I = ne .: N = I/e = 0.01 x 1019 = 6.25 x 1016 electrons
1.6
iii) ev = 1/2 mev2
.:
√
1
31
= 7.262 x 107 m/s
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KIGUMO SUB-COUNTY CLUSTER EXAM 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
MARKING SCHEME
QUESTION 1
C (iv)
(NB - These values are only a guide. They are subject to change depending on the type of spring used. Recommended to use the
student’s values)
All tables values correct 9 marks
d) i) Scale
Axis labelled with quantities and units
Plotting
d) ii) Correct substitution
iii) Correct T2 intercept
Substitution
b) ii) Slope of the graph
1.44 – 1.06 s2
30 – 20
cm
= 0.038s2/cm
iii) 4 p2 = 0.38
b
b = 4p2
0.038
= 1039
QUESTION 2
d) 600
i) Values of d decrease, then increase. Mark the trend. (8 marks)
Scale
Axis labelled
Plotting
Curve
(h) Read from the graph the minimum value for d (30 0)
(p) Numerator and evaluated
Denominator and evaluated
Substitution
Accuracy, n = 1.5
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232/1,232/2,232/3 physics
KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
1. The figure below shows the reading obtained on a vernier caliper that has a zero error of -0.12cm, when measuring the
diameter of a metal ball
Determine the diameter of a metal ball.
(2mks)
0
0
2. The length of mercury thread in a thermometer at 0 C is 4cm, while the length at 100 C is 20cm. What is the temperature
when the length is 12cm?
(2mks)
3. The figure below show a glass tumbler filled with water to the brim, a card made of manila paper is then placed on top of a
glass tumbler as shown in figure 1.
Tumbler filled with water
Tumbler filled with water
upright
upside down
While supporting the card with one hand the glass tumbler is carefully inverted as shown in figure (ii). It is observed that
the card remains in place without being support. Explain this observation.
(2mks)
4. A spring has a spring constant of 40N/m, if the extension on the spring is 6.0cm, determine the tension on the spring. (2mks)
5. When loosening a nut mechanics prefer to use a long spanner than to use a short one. Explain why?
(2mks)
6. A bullet of mass 10g is fired at 200m/s from a pistol of mass 1.0kg. What is the recoil velocity of the piston.
(2mks)
7. Some candle wax is placed at one end of each of the aluminium rods with different thickness. The rods are than heated in a
candle flame as shown in the figure below.
State and explain the observation made.
8.
(2mks)
3
An oil drop spreads on the surface of water to a diameter of 14cm. If 50 such drops occupy 0.0035cm . Estimate the diameter
of the oil molecule.
9. A uniform metre rule is balanced as shown below.
(2mks)
Find the weight of the metre rule.
(2mks)
10. State the role of the volatile liquid in a refrigerator.
(1mk)
11. A body of mass 5kg is placed at a height 20m above the ground. Calculate the velocity at which it strikes the ground when it
is released to fall freely.
(2mks)
12. Sketch a velocity-time graph for an object thrown vertically upwards until it gets back to it’s back to it’s initial position.
(2mks)
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13. A liquid flows along a horizontal pipe of cross-section area of 20cm2 at a speed of 3.0m/s. If the speed increases to 9.0m/s
when it reaches a narrow section, determine the cross-section area of the narrow section.
(2mks)
14. (a) An object immersed in water feels lighter than when in air. Explain the observation.
(2mks)
3
(b) The weight of a solid in air is 6.0N. When it is fully immersed in a liquid of density 950Kg/m , Its weight is 5.05N.
Determine
i) the upthrust in the liquid.
(1mk)
ii) the volume of the solid.
(2mks)
(c) In an experiment with a metal cube, the following results were obtained;Weight of the cube in air
0.6N
Weight of the cube completely immersed in water
0.54N
Weight of the cube completely immersed in liquid
0.56N
Calculate the relative density of the liquid
(3mks)
(d) i) State how pressure of a liquid varies as its speed increases.
(1mk)
3
ii) 500cm of fluid flows out of a tube in 25 seconds. If the inner diameter of the tube is 1.4cm, what is the average
velocity of the fluid in the tube?
(2mks)
15. (a) Define the term efficiency of a machine.
(1mk)
0
b) The figure below show a drum of mass 80kg being rolled up a plane inclined at 30 to the horizontal. The force applied is
420N and the distance moved by the drum along the plane is 5.0m.
Calculate :
(i) The work done by the effort
(ii) the work done in rising the drum.
(iii) the efficiency of the inclined plane as a machine.
(c) A stone is released from the top of a cliff 45m high with a horizontal velocity of 20m/s as shown in
below.
Calculate:(i) the time it takes to hit the water surface.
(ii) the velocity with which it hits the water.
(iii) the horizontal distance moved R (1mk)
16. (a) What is meant by absolute zero temperature.
(b) The figure below shows a set up to investigate the relationship between volume and temperature of
(i) State two factors that are kept constant in order to determine the relationship.
(ii) Explain the function of the sulphuric acid.
(iii) State the law being investigated in the experiment.
(iv) The volume of the gas at 200C was found to be 100cm3. What would be its volume at 400C.
(2mks)
(2mks)
(2mks)
the figure
(2mks)
(2mks)
(1mk)
a certain gas.
(2mks)
(1mk)
(1mk)
(2mks)
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232/1,232/2,232/3 physics
(c) A mixture consist of 40cm3 of water and 60cm3 of liquid x. If the density of water and liquid x are
0.8g/cm3 respectively, calculate the density of the mixture.
17. (a) Name two forces acting on a racing car, when racing along curved road.
(b) A particle on a wheel moves through an angle of 600 in 0.2 seconds, if the radius of the wheel is
1.0g/cm3and
(3mks)
(2mks)
30cm determine the
(i) Angular velocity of the wheel.
(2mks)
(ii) Linear speed of the particle.
(2mks)
(c) The figure below shows two trolleys of mass 5.0kg and 3.0kg travelling towards each other at 0.60m/s and 0.5m/s
respectively.
If the trolleys fuse on collision. Calculate the velocity of the combined trolleys.
(ii) A goalkeeper catches a ball of mass 450g moving with a velocity of 20m/s. Determine
(I) momentum of the ball.
(II) the average force applied by the goalkeeper hands to stop the ball in 0.4 seconds.
18. (a) Define the term specific latent heat of fusion.
(b) The figure below show an incomplete set up that can be used in an experiment to determine the
fusion of ice by electric method.
i) Complete the diagram by inserting the missing components for the experiment to work.
ii) The following readings were noted after the heater was switched on for 10 minutes.
Mass of the beaker
150g
Mass of beaker + melted ice
200g
Current through the heater
2A
Voltage across the heater
15V
Determine the
(I) Energy supplied by the heater in the 10 minutes.
(2mks)
(2mks)
(2mks)
(1mk)
specific latent heat of
(2mks)
(2mks)
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232/1,232/2,232/3 physics
KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
1. A lady holds a large concave mirror of focal length 80cm, 60cm from her face. State two characteristics of her image in the
mirror.
(2mks)
2. Figure 1 below shows a wire XY at right angles to a magnetic field. XY is part of circuit containing a galvanometer.
3.
4.
5.
6.
7.
8.
9.
Figure 1
When XY is moved the current flows in the direction shown. State the direction in which XY is moved.
(1mk)
State two distinctions between the way sound waves and electromagnetic waves are transmitted.
(2mks)
A soldier standing some distance from a wall blows a whistle and hears its echo 3.6 seconds later. How far is the wall from
the soldier?
(Speed of sound in air is 360m/s)
(3mks)
A ray of light incident on the surface of a glass prism is observed to behave as represented in figure 2 below.
Figure 2
Explain this observation.
(3mks)
Figure 3 shows a cross-section of an optical fibre made of two types of glass A and B. The refractive index of B is lower than
that of A.
Figure 3
A ray of light enters the optical fibre at P and emerges from Q.
(i) Sketch the path of the ray through the fibre.
(1mk)
(ii) State the reason why light travels through the fibre as in (i) above.
(1mk)
In large current circuits large resistors in parallel are preferred to low resistors in series. Explain.
(2mks)
A wire is stretched between two fixed points such that when it is plucked, it produces sound. Explain why the pitch of the
sound produced may become lower when the temperature of the surrounding rises.
(2mks)
Figure 4 shows water waves incident on a shallow region of the shape shown with dotted line
Figure 4
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232/1,232/2,232/3 physics
On the same diagram, sketch the wave pattern in and beyond the shallow region.
(1mk)
10. Figure 5 shows two charged identical conducting spheres on insulating stands. Each cross represents a charge. The spheres
are briefly brought into contact.
Figure 5
Sketch in the space provided the diagrams of the spheres showing charge distribution after separating.
11. Figure 6 shows three capacitors connected between two points A and B.
(2mks)
Figure 6
Determine the capacitance across AB.
12. State two factors other than the speed of rotation that affect the magnitude of the induced e.m.f. generated.
13. Figure 7 shows a simple generator. The coils are rotated in the anticlockwise direction as shown.
(3mks)
(2mks)
14.
Figure 7
(a) Name the parts labelled P and Q.
(2mks)
(b) Indicate using arrow on the figure the direction of the induced current as the coil passes the
position shown.
(1mk)
(c) State two ways of increasing the magnitude of the induced current in this type of generator.
(2mks)
(d) On the axis provided, sketch the graph on the induced e.m.f. with time.
(2mks)
(e) The section marked XY is cut off and a diode inserted. On the axis provided, sketch the graph of
p.d. across the resistor R, against time.
(1mk)
Figure 8 shows a section of a house wiring system.
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232/1,232/2,232/3 physics
a) Name the
(i) circuit labelled P
(1mk)
(ii) terminals labelled X and Y
(2mks)
(b) i) State the purpose of R in the circuit.
(1mk)
(ii) Give a reason why R is connected to Y but not to X.
(1mk)
(c) Determine the cost of using the electric iron rated 150W for a total of 30 hours given that the cost of electricity per
KWh is Ksh 8.
(1mk)
15. Figure 9 below shows a cathode ray tube in which a beam of electrons is cast on the screen
Figure 9
(a) State how the electrons are produced in the tube.
(b) State how the electron beam is detected.
(c) State the reason for having a variable potential difference (p.d) at the:
(i) Grid
(ii) Anodes
(d) Figure 10 shows the waveform of a signal applied at the Y- plates of an oscilloscope whose
time-base is switched to the scale of 2 milliseconds per centimetre.
(1mk)
(1mk)
(1mk)
(1mk)
Figure 10
Determine
(i) the period of the signal
(2mks)
(ii) the frequency of the signal.
(3mks)
16. (a) State two factors that determine the speed of photoelectrons emitted by a metal surface.
(2mks)
(b) In an experiment using a photocell, a u.v. light of varying frequency but constant intensity was
made to strike a metal surface. The maximum kinetic energy (k.e. max) of photoelectrons for each
frequency, f, was measured. The graph shows how KE max varies with f.
Given that KE max = h f – O, determine the values of h and O from the graph.
h=
(3mks)
O=
(3mks)
(c) Light of frequency 5.5 x 1014Hz is made to strike a surface whose work function is 2.5 eV. Show that photoelectric effect
will not take place.
(3mks)
17. (a) The initial mass of a radioactive substance is 20g. The substance has a half-life of 5 years. Determine the mass remaining
after 20 years.
(2mks)
(b) When a radiation was released into a diffusion cloud chamber, short thick track were observed. State with a reason, the
type of radiation that was detected.
(2mks)
(c) Radium undergoes radioactive decay by emitting an alpha particle to form a daughter nuclide Q as in the reaction.
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232/1,232/2,232/3 physics
Determine the values of
(i) x
(ii) y (1mk)
18. Figure 11 below shows a alternating current (a.c.) connected across a diode D and a resistor R.
(1mk)
Figure 11
(a) On the axis provided sketch the output as observed in C.R.O. connected across R.
(1mk)
(b) When a germanium crystal is doped with arsenic, it becomes an N-type semiconductor. Explain how the change
occurs. (Number of electrons in the outmost shell for germanium 4, Arsenic = 5)
(2mks)
(c) The graph shows current against voltage for a semiconductor diode.
In the space provided, draw a circuit diagram that may be used to obtain values needed to draw the above graph. (2mks)
19. Figure 12 shows an electrical circuit including three switches, S 1, S2, and S3 and three identical lamps L1, L2 and L3. A
constant potential difference is applied across X and Y.
(i) Other than L1, state the lamp that will light when S1 and S2 are closed.
(ii) How does the brightness in L1 in (i) above compare with it’s brightness when all the switches are closed.
(iii) Explain the observation in (ii) above.
20. You are provided with the following apparatus to determine the focal length of a lens.
 A biconvex lens and lens holder
 A lit candle
 A white screen
 A metre rule
(a) State two measurements that you would take.
(b) Explain how the measurements in (a) above would be used to determine the focal length of the
lens.
(c) Describe the procedure you would follow in determining the focal length of the above lens.
(d) Draw a diagram to show how you would arrange the above apparatus to determine the focal
length of the lens.
(1mk)
(1mk)
(2mks)
(2mks)
(2mks)
(1mk)
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-
KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
CONFIDENTIAL
Question 1
Voltmeter which can measure to up 5 volts
Two new dry cells
A cell holder that can connect in series
A resistor labelled R of 3.9
A micrometer screw gauge (can be shared).
A nichrome wire SWG 28 mounted on a mm scale of length 1m
Six connecting wires all least four with crocodile clips
A switch
A biconvex lens labelled L (Focal length 10cm)
A full candle
A metre rule
A piece of plasticine
-
Question II
A spiral spring - that support 250g
Five 50g masses or one 50g mass and two 100g masses
A complete retort stand
Two wooden pieces
A half metre rule or a metre rule
A weighing balance (can be shared)
KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
QUESTION 1
PART 1
1. You are provided with the following
- A voltmeter
- Two dry cells and a cell holder
- A switch
- A resistor labelled R
- A wire mounted on a mm scale and labelled G
- A micrometer screw gauge (to the shared)
- Six connecting wires with six crocodile clips
a)
Proceed as follows
Record the length L0 of the wire labelled G
L0 =
..................................... (1mk)
Use the micrometer screw gauge provided to measure the diameter of the wire labelled G at two different points and
determine the average diameter, d
The diameter d1 = .......................mm, d2 ................. mm
(1mk)
b)
Average diameter d = .................... m
Determine the radius of the wire in metres.
Set up the apparatus as shown in the circuit diagram in figure 1 shown below.
(1mk)
Figure 1
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232/1,232/2,232/3 physics
i) Use the voltmeter provided to measure the p.d. V R across R and p.d VG across G when the
switch is closed.
VR = .......................... volts
VG = ........................... volts
(1mk)
(1mk)
Open the switch
ii) Use the value of R provided and the value of V R in b(i) above to calculate the current I flowing
through R when the switch was closed.
I = ........................ Amperes
(1mk)
iii) Determine the constant H given that
H = 100VG
1 x L0
H = ........................... (1mk)
QUESTION 1
PART 2
1. You are provided with the following apparatus:
- A biconvex lens labelled L
- A candle
- A lens holder
- A metre rule
- A piece of plasticine
Proceed as follows
c) Arrange the candle, lens, screen and metre rule as shown. Ensure that the flame of the candle is at the same level as the centre
of the lens, L. This may be done by raising the candle with a piece of plasticine as it gets shorter.
d) With the lens placed 20cm from the candle, adjust the position of the screen till a sharp image of
the candle is formed on it. Read and record the value of V.
e) Increase U in steps of 5cm and obtain the corresponding values of V. Complete the table.
(5 marks)
(i) Plot a graph of object distance, u (y - axis) aganist the ratio U/V
(ii) Determine the slope, S of the graph.
QUESTION 2
You are provided with the following:
• A spiral spring
• Five 50g masses or one 50g mass and two 100g masses
• A complete retort stand
• Two wooden pieces
• A half metre rule or a metre rule
• A weighing balance
Proceed as follows:
(a) Clamp the spiral spring and a half meter rule onto the retort stand.
Record the position of the pointer when no mass is attached to the end of the spiral spring.
Reading of the pointer .................... cm
(2mks)
(1mk)
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232/1,232/2,232/3 physics
b) Suspend the 50g mass to the spring and displace it slightly downwards and measure the time for 20 oscillations. Repeat the
procedure for 100g, 150g, 200g and 250g masses and record your results in the table below.
(6mks)
c) Plot a graph of T2 against extension, e
e) Given that the relationship bwtween R and e is
T2 = 42 e + 4 m
g
k
Find the value of ‘g’. (take  = 3.142)
f) Using the weighing balance, measure and record the mass, m, of the spiral spring.
Mass of spring = ............................... kg
g) Determine the vertical intercept and hence find the value of ‘k’
(5mks)
(2mks)
(2mks)
(1mk)
(3mks)
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KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
MARKING SCHEME
1. Reading = 2.6 + (6 x 0.01) = 2.66cm
Diameter of ball = 2.66 + 0.12
= 2.78cm
0
2.
100 = (2- 0 4) = 16cm
1cm = 1000C
16
12cm = 1000C x 12 = 750C
16
3. The atmospheric pressure is greater than the pressure due to the water in the glass tumbler.
Atmospheric pressure acts in all direction.
4. F = Ke
F = 40 x 0.06
F = 2.4N
5. A long spanner exerts a larger moment of force for the same amount of force.
6. Momentum before firing = momentum after firing
1.0 x 0 + 0.01 x 0 = 1.0v + 0.1 x 200
V = - 0.01 x 200
1.0
V = -2m/s
7. - Candle wax on thicker road falls faster compared to the thin rod
- Thicker conductor conducts heat faster than thin conductor.
8.
Volume of patch = Volume of drop
r2d = 0.035
50
22 x 7 x 7 x d = 0.0035 = 0.00007
7
50
d = 0.00007
22 x 7
d = 4.5 x 10-7cm
9. Clockwise moment = anticlockwise movement
30 x w = 20 x 5.0
w = 20 x 5 = 3.333N
30
10. Volatile liquid removes heat when it vaporizes and takes in latent heat.
11. V2 = u2 + 2gs
V2 = 0 + 2 x 10 x 20
V = √4
V = 20m/s
12.
13. a1v1 = a2v2
20 x 3.0 = 9.0 x a2
a2 = 20 x 3.0
9.0
2
a = 6.67cm2
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14. (a) It experiences an upthrust force which tend to push the weight of the object upwards.
(b) (i) Upthrust = 6.0 – 5.05 = 0.95N
(ii) Upthrust = Veg
0.95 = V x 950 x 10
V=
0.95
950 x 10
V = 0.0001m3
(c) R.d =
Upthrust in liquid L
Upthrust in water
R.d. = 0.6 – 0.56
0.6 – 0.54
R.d = 0.667
(d) (i) Fluid pressure reduces as the speed of the fluid increases.
(ii) Volume flow rate = Area x velocity
500 = 22 x 0.7 x 0.7 x V
25
7
V=
20
= 12.99cm/s
22 x 0.1 x 0.7
15. (a) Efficiency is the ratio of work output to work input expressed as a percentage
or efficiency = Work output x 100%
Work input
Efficiency = M.A. x 100%
V.R.
(b) i) Work input = F x d
= 420 x 5
= 2100J
ii) Work output = mgh
= 80 x 10 x 5 Sin 300
= 2000J
iii) Efficiency = Work output x 100%
work input
= 2000 x 100
2100
= 95.24%
(c) i) S = ut + 1/2gt2
4s = 0 + 1/2 x 10 x t2
t = 9 = 3s
ii) V = u + gt
V = 0 + 10 x 3
V = 30m/s
iii) R = ut
R = 20 x 3
= 60m
16. (a) It is lowest temperature a gas can fall to (-2730C)
(b) i) Mass of the gas, the pressure of the gas.
ii) To dry the gas
iii) Charle’s law, the volume of fixed mass of gas is directly proportional to its absolute
temperature at constant pressure.
iv) V1 = V2
T 1 T2
100 = V2
293
313
V2 = 100 x 313 = 106.83cm3
293
c) Total volume = 60 + 40 = 100cm3
Mass of water = ev = 1 x 40 = 40g
Mass liquid x = 0.8 x 60 = 48g
Total mass = 40 + 48 = 88g
e of mixture = total mass
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232/1,232/2,232/3 physics
total volume
= 88
100
= 0.88g/cm3
17. (a) - Friction between the wheel’s and the road
- Centripetal force
- Normal reaction on the wheel of the car
(b) i)  = O
t
 = 60 x 2
360 x 0.2
ii) V = wr
V = 5.237 x 0.3
= 1.571m/s
(c) i) Total initial momentum = Total Final momentum
or m1u1 + m2u2 = (m1 + m2) V
(5 x 0.6 + (-3 x 0.5) = (5 + 3)V
V = 1.5 = 0.1875m/s
8
(ii) (I) Momentum = mv
= 0.45 x 20
= 9kgms-1
(II) Ft = change in momentum
F x 0.4 = 0 - 9
F = -9 = -22.5 N
0.4
18. (a) Is the quantity of heat required to convert a unit mass of substance from solid to liquid state without change in temperature.
(b) (i)
(ii) E = VIt
E= 15 x 2 x 10 x 60
E = 18000J
(iii) MLf = VIt
0.05 x Lf = 18000
Lf = 18000
0.05
5
= 3.6 x 10 J/Kg
(c) Q = MC O
Q = 0.05 x 450 x (80 - 25)
= 1237.5J
Rules on marking numerical questions
Formula
1mk
Substitution 1mk
For question with two marks
1st mark is at formula or correct substitution
Correct value with correct unit, 1mk
1/ mk
Correct value with no unit
2
Correct answer with wrong unit, 0mk
no mark
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KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
MARKING SCHEME
1. - Virtual
- Erect or as upright as the object
- Magnified
2. Downwards
3. Transmission of sound waves requires a material medium but no material medium is required for electromagnetic waves.
4. V = 2d
t
360m/s = 2d
3.6
d = 360 x 3.6
2
d = 648m
5. White light consists of several colours, each with a different wavelength. Every colour therefore travels with a different velocity
in glass, so each colour is deviated differently causing dispersion.
6. (i)
(ii) Light undergoes total internal reflection.
7. Parallel resistors allow diversion of current, hence will not overheat.
8. The wire expands or becomes longer and its tension reduces and this lowers the frequency hence the pitch.
9.
10.
11.
3F + 4F = 7F
1 = 1 + 1
C 2
7
1 =7+2= 9
C
14
14
C = 14
9
C = 1.56 F.
12. - Number of turns or coils of the wire
- Strength of the magnetic field
- Angle of inclination between the wire and the magnetic field.
13. (a) P = Slip rings
Q = Carbon brushes
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(b)
(c) - Increasing the number of turns
- Increasing the speed of rotation
- Using stronger magnets
(d)
(e)
14. (a) (i) P = Main Ring Circuit
(ii) X = Neutral wire
Y = Live wire
(b) (i) To guard against excess current
(ii) To ensure that when R breaks, the appliance does not remain live,
c) Cost of electricity = 1.5Kw x 30h x 8 sh= Ksh 360
15. (a) Thermionic emission i.e. the filament heats up the cathode
(b) A spot is seen on the screen
(c) (i) To focus the electrons towards the screen
(ii) To accelerate the electrons toward the screen
(d) i) One wave = 2 x 2ms = 4ms
= 4 x 10-3s = 0.004s
ii) f =
1 = 1
T
0.004
= 250Hz
16. (a) - Frequency of the incident light
- Work function of the metal surface
(b) From k.e. = hf - O
then h = slope
Slope = ke = (9.3 – 6) x 10-19
f
= 3.3 x 10-19
0.5 x 1015
(2.5 – 2) x 10-15
h = 6.6 x 10-34Js
From k.e. = hf – O
k.e. = hf – hfo
then hfo = y – intercept = work function
so
O = hfo = 6.6 x 10-34 x 1.1 x 1015
= 7.26 x 10-19J
c) Max k.e. = hfo
= 6.6 x 10-34 x 5.5 x 1014
= 36.3 x 10-20
= 3.63 x 10 -19J
In eV = 3.63 x 10-19 = 2.27 eV
1.6 x 10-19
No photoelectric will take place since hfo is less than the work function ie ( hfo <Wo)
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17. (a) After every 5 years the half the mass decays ie
20g ----> 10g ----> 5g---- > 2.5g ---->1.15g
OR
N = No(1/2)T/t
= 20 (1/2)20/5 = 20 (1/2)4
= 20 (1/16) = 20/16 = 1.25g
This radiation has a short range with intense ionisation hence thick tracks.
i) x = 222
y = 86
18. (a)
(b) Four electrons from arsenic bond covalently with germanium leaving a free electron that is responsible conductivity.
(c)
19. (a) (i) L2
(ii) L1 is brighter
iii) When the switches are all closed the total resistance is less.
20. (a) Distance of the candle from the lens or object distance (u)
- Distance of the screen from the lens or image distance (v)
(b) Draw a graph of magnification against image distance then get the reciprocal of the gradient (slope) as the focal length.
(c) - Candle is placed at a certain distance from the lens.
- The distance between the screen and the lens is adjusted until a sharp image is focused on the screen.
(d)
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1.
KIRINYAGA WEST SUB-COUNTY EFFECTIVE “40” EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
MARKING SCHEME
(a) L0 = 100cm or 1m
Diameter d1 = 0.26mm
Diameter d2 = 0.26mm
Average diameter d = 0.26 + 0.26
2
= 0.26mm = 0.00026m
Radius r = 0.00026 = 0.00013 m
2
(b) VR = 2.1 volts + 0.2
1mk
VG = 2.4 volts + 0.2 1mk
I = V = 2.1 = 0.54A
R
3.9
ii) Determination of constant H
H = 100VG
I x L0
= 100 x 2.4 = 444.4 1m
0.54 x 1 
Slope ‘S’ = y
x
=
45 – 20
2.459 – 0.7142
=
25
1.7448 = 14.3283cm
 y
x
Correct intervals from
Candidates graph
Correct evaluation with
Units to 3 s.f. ( units S2/cm)
-
(1 mk)
(1mk)
4 2 = Slope - 1/2mk correct substitution

g
for  & slope =
Correct evaluation Mass of spring in kg - must be to five decimal place
Vertical intercept - Must be correct from candidates
graph - 1mk
42 = Vertical intercept K
Correct substitution for 
and vertical intercept Top grade predictor publishers
1mk)
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232/1,232/2,232/3 physics
GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
1. The figure 1 below shows a micrometer screw gauge that has a zero error of +0.02. State the actual reading of the micrometer
screw gauge.
(1 mark)
25
20
15
Fig 1
2. In the figure 2, below, U-tube contains two immiscible liquids P and Q. If the density of Q is 900kg/m³ and that of P is 1200kg
/ m³, Calculate the height of liquid Q.
(3 marks)
P
Q
h
9cm
3cm
Fig 2
3. Distinguish between latent heat of fusion and specific latent heat of fusion of a substance.
(1 mark)
4. A mass of 8kg is whirled round in a horizontal circle using a rope that is 80cm long, it is takes 2½ circles in 1 second, calculate
the tension the rope experiences.
(3 marks)
5. Fig 3 shows a solid cylinder standing on a horizontal surface. The cylinder is in stable equilibrium.
Fig 3
On the horizontal space provided, sketch the cylinder in neutral equilibrium
(1 mark)
6. In terms of intermolecular forces, explain the difference between liquid and gaseous state.
7. (a)Under what conditions can a feather and a stone released from the same height land on the ground at the same time?
(b) On the axis on figure 4 below, sketch displacement time graph for accelerating body.
(1 mark)
Displacement
(m)
Time (s)
Fig 4
8. A spring extends by 4cm when a load of 10N is suspended from it. Six similar springs are used in the system shown in figure
5. Determine the total extension.
(3 marks)
50 N
Fig 5
9. Explain how heat loss by radiation is minimized in a vacuum flask.
(1 mark)
10. A pipe of radius 2mm is connected to another pipe of radius 6mm. If water flows in the narrow pipe at a speed of 3m/s,
determine the speed of water in the wider pipe.
(3 marks)
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Fig 6 shows the features of a dry cell (leclanche). Using the information in the figure to answer questions 11 and 12.
A
D
C
B
Fig 6
11. State the polarities of the parts labelled A and B.
(1 mark)
12. Name the chemical substances in the parts labelled C and D.
(2 marks)
13. The light uniform bar in figure 7 is in equilibrium. The two beakers A and B contain water at the same temperature. The two
blocks are made of the same material.
Water
Water
A
B
Fig 7
If the temperature of the water in beaker A is now raised, explain why the beam tips to side A. Assume the solid does not
expand.
(2 marks)
14. A stone thrown vertically upwards from the base of a mountain with an initial velocity of 100m/s. The stone just stopped as
the apex and came back. Another boy projected a stone horizontally from the top of the mountain. Calculate:
(a) Height of the mountain.
(2 marks)
(b) Time taken for the stone to follow the trajectory.
(2 marks)
(c) The range if the horizontal velocity is 20m/s.
(2 marks)
(d) Calculate the impulse of force produced when a table is pulled for 3 seconds by a constant force of 10N towards the right
and then for 2 seconds by a constant force of 20N towards the left.
(2 marks)
(e)The figure 8 below shows a tape from a trolley accelerating at 5m/s and the timer is vibrating at 100HZ.
B
A
Tape
0.125
Fig 8
(i) Change in velocity from A to B.
(2 marks)
(ii) The final velocity of the trolley.
(2 marks)
15. (a) Two gear-wheel have 80 teeth and 20 teeth and they lock with each other. They are fastened on axles of equal diameter
such that equal weight of 150N attached to the string around the axle will just raise 450N on the other axles. Calculate
(2 marks)
(ii) The velocity ratio.
(2 marks)
(iii) The efficiency of the machine.
(2 marks)
(b) (i) A loudspeaker is a transducer. Explain.
(1 mark)
(ii) Explain the energy change that occur when a man climbs the mountain.
(1 mark)
(c) Calculate the total power in lifting 0.2kg of metal cane containing 2000cm³ of ice onto a lorry as shown below within 4S.
Density of ice is 0.9g/cm³
(3 marks)
open
Closed
3m
2m
16. (a) What is meant by term specific latent heat of vaporization?
(1 mark)
(b) In an experiment to determine the specific latent heat of vapourisation of water, steam at 100°C was passed into water
contained in a well lagged copper calorimeter. The following measurements were made :Mass of calorimeter = 50g
Initial mass of water 70g
Initial temperature of water = 5°C
Final mass of water + Calorimeter + condensed steam = 123g
Final temperature of mixture = 30°C
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Specific heat capacity of water = 4200jKg-1k-1
Specific heat capacity of copper = 392jKg-1k-1
I. Determine the:(i) Mass of condensed steam.
(1 mark)
(ii) Heat gained by water and calorimeter.
(2 marks)
II. Given that L is the specific latent heat of vaporization of steam.
(i) Write an expression for the heat given out by steam.
(1 mark)
(ii) Determine the value of L.
(3 marks)
III. The specific latent heat of fusion of ice is 334J/g. Explain what this means.
(1 mark)
IV. The specific heat capacity of pure water is 4200J/ kg /k while that of sea water is 3900J/kg/k. Which of the two
liquids is the most appropriate to be used in cooling systems. Give a reason.
(2 marks)
17. (a) State the law of floatation.
(1 mark)
(b)The figure 10 below represents a sphere 0.012m³ volume and mass 5kg floating between two liquids A and B such that 2/3
of its volume is in liquid A. Density of liquid B is 800kg/m³
(Take g = 10N/kg).
Liquid A
Liquid B
Fig 10
Determine
(i) Weight of liquid B displacement.
(2 marks)
(ii) Weight of liquid A displaced.
(1 mark)
c) The sphere is now anchored at the base of the container that ¼ of its volume is in liquid A. Find the tension in the string.
(3 marks)
d) Explain why a hydrometer has the following:
(i) Lead shots in the bulb.
(1 mark)
(ii) Narrow stem.
(1 mark)
18.( a) State Newton's second law of motion.
(1 mark)
(b) A wooden block resting on a horizontal bench is given an initial velocity, U, so that it slides on the bench surface for a
distance, d, before coming to stop. The values of d were measured and recorded for various values of initial velocity.
Figure 11 shows the graph U² against d.
U²(m/s)²
150
100
50
0
Fig 11
5
10
15
d(m) 20
25
(i) Calculate the slope S of the graph.
(3 marks)
(ii) Given that U² = 20kd, where k is a constant for the bench surface, determine the value of k from the graph.
(2 marks)
(iii) State how the value of K would be affected by a change
in the roughness of the bench surface.
(1 mark)
-2
(c) A care of mass 800kg starts and accelerates at 1.2ms . Determine its momentum after it has moved 400m from the starting
point.
(3 marks)
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232/1,232/2,232/3 physics
GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
1. The figure 1 below shows the image I behind a mirror M
M
Eye
I
Fig 1
Using ray diagram construction, locate the position of the object.
(2 marks)
2. An electromagnet is made by winding insulated copper wire on an iron core. State two changes that could be made to increase
the strength of the electromagnet.
(2 marks)
3. The diagram below shows an electrical appliance connected to the mains.
A
Fuse
Casing
Heating
element
B
Fig 2
I. Name the colour codes for leads A and B
II. What is the purpose of the fuse.
4. State one differences between an image formed by a plane mirror and that observed through a pinhole camera.
5. Figure 3 shows a combination of capacitors across a power supply.
(2 marks)
(1 mark)
(1 mark)
100 f
100 f
200 f
Fig 3
400 f
20V
Displacement(m)
Determine the energy stored in the system of capacitors.
6. An electric bulb is rated 75W, 240V. Determine the resistance of the bulb.
7. Figure 4 shows how the displacement varies with time for a certain wave.
(3 marks)
(2 marks)
0.4
0.2
-0.2
0.5
1.0
1.5
2.0
2.5
Time(minutes)
-0.4
Fig 4
Determine the frequency of the wave.
(2 marks)
8. In an X-rays tube it is observed that the intensity of X-rays increases when the potential difference across the filament is
increased. Explain this observation.
(2 marks)
9. Explain why a p-n junction diode will conduct when connected in forward bias.
(1 mark)
10. Give a reason why lecture theatre halls are covered with soft perforated materials.
(1 mark)
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232/1,232/2,232/3 physics
11. Figure 5 shows a magnet being moved towards a stationary solenoid. It is observed that a current flows through the circuit in a
direction Q to P.
N
S
Motion
P
Q
Fig 5
Explain :
(i) How the current is produced.
(ii) Why the current flows from Q to P.
12. Figure 6 shows an object placed infront of a prism as shown.
(2 marks)
(1 mark)
eye
45°
45°
Using two rays show the image of the object as observed by an observer at E.
13. Table 1 below shows the radiations and their respective frequencies.
Frequency
Yellow light
1 × 105
Gamma rays
1 × 1022
Arrange the radiations in the order of increasing energy.
14. (a) Figure 7 shows a connection of the three pin plug.
Brown
Green/
Yellow
1 × 106
(2 marks)
Micro waves
1 × 1011
(1 mark)
Blue
(i) Identify two mistakes in this wiring.
(2 marks)
(ii) What would happen if this plug was connected to the mains of the socket?
(1 mark)
(iii) State two reasons why the earth pin is normally longer than the other two pins.
(2 marks)
(b) A house has five rooms with 240V, 60W bulbs. If the bulbs are switched on from 7.00pm to 10.30pm
(i) Calculate the power consumed per day in kilowatt-hours.
(3 marks)
(ii) Find the cost per week for lighting these rooms at Kshs 670 per unit.
(2 marks)
15. (a) (i) Distinguish between threshold frequency and threshold wavelength.
(1 mark)
-7
(ii) The maximum wavelength required to cause photoelectric
emission on a metal
surface is 8.0
×-1 10 m. The metal
14
-34
8
surface is irradiated with light of frequency 8.5 × 10 HZ. (Take h = 6.62 × 10 Js, C=3.0 ×10 ms )
Determine
I. The threshold frequency.
(2 marks)
II. Maximum kinetic energy of the electrons.
(3 marks)
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232/1,232/2,232/3 physics
b) The graph below in figure 7 shows the variation of stopping
potential Vs, against reciprocal of the wavelength, 1/l for a certain
metal. If the work function of the metal was 2.08 × 10 -19 and velocity of electromagnetic wave is 3.0 × 108 ms-1
30
-1
VS X 10 (V)
25
20
15
10
5
0
5
10
15
20
25
1
-1
30
7
/ (m ) X 10
-5
-10
-15
Fig. 7
hc WO
The equation of the graph is given by
use the graph to determine
V( S ) 

(i) the slope of the graph.
(3 marks)
e
e
(ii) the value of the electronic charge.
(4 marks)
16. (a) Distinguish between e.mf. and terminal voltage of a battery.
(2 marks)
(b) The graph in figure 8 shows the variation of potential difference V against current I for a cell when current is drawn from
it.
2.0
1.5
1.0
0.5
Fig 8
0
0.2
0.4
0.6
0.8
1.0
1.2
(i) From the graph determine
(a) The e.m.f of the cell.
(2 marks)
(b) The internal resistance of the cell.
(4 marks)
(c) on the space provided below, draw a circuit that could be used to obtain the results represented by the graph.
(2 marks)
(d) Figure 9 shows an electric circuit. When the switch is closed the ammeter reading is 0.3A. Neglect internal resistance.
10v
A
10
1amp
V
Page | 220
232/1,232/2,232/3 physics
Fig 9
17. Figure 10 below shows parallel rays of light incident on a convex lens.
F
(2 marks)
F
Complete the ray diagrams to show the emergent beam in each case.
(2 marks)
(b)Table 2 below shows values of object distance U and corresponding value of image distance V for a convex lens.
Object distance U (cm)
10
15
20
25
30
35
Image distance V (cm)
24.6
17.1
13.3
11.8
10.9
10.4
Table 2
(i)Plot a graph of (U + V) against UV.
(5 marks)
(ii) Determine the focal length of the lens.
(3 marks)
(c) Give one difference between the eye and the camera.
(1 mark)
18.(a)(i) State Faraday's law of electromagnetic induction.
(1 mark)
(ii) State the difference between induction coils and a step-up transformer.
(1 mark)
(b) An ideal transformer steps 8.0V upto 2000V, and the 4000 turns secondary coil carries 2.0 Amps.
Calculate.
(i) The number of turns in the primary coil.
(2 marks)
(ii) the current in the primary coil.
(2 marks)
(c) Figure 9 below shows a diagram of a bicycle dynamo. Wheel A is connected by an axle to a permanent cylindrical magnet
and is rotated by the bicycle wheel.
Bulb
S
N
A
Soft iron
(i) Explain why the bulb lights.
(ii) How would the person riding the bicycle make the bulb brighter.
(2 marks)
(1 mark)
Page | 221
232/1,232/2,232/3 physics
GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3
CONFIDENTIAL INSTRUCTIONS
The information in this paper is to enable the head of the school and the teacher in charge of Physics to make adequate
preparations for this year's Physics practical examination. NO ONE ELSE should have access to this paper or acquire knowledge
of it’s contents. The teacher in charge of physics should NOT perform any of the experiments in the same room as the candidates
or make the results of the experiment available to the candidates or give any other information related to the experiments to the
candidates. Doing so will constitute an examination irregularity which is PUNISHABLE.
Each candidate should be provided with the following:
Question 1





Saturated salt solution in 500ml beaker.
Two identical cylindrical 100g masses
A retort stand.
A metre rule
Question 2








Ammeter
A voltmeter
A wire labelled X on a mm scale (Gauge 32)
A switch
A jockey
Three new size D dry cells.
Six connecting wires with crocodile clips at both ends.
Three cells holders.
GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
Question 1
You are provided with the following.
- Saturated salt solution in 500ml beaker.
- Two identical cylinder masses of 100g
- A retort stand.
- A metre rule.
a) Determine the volume V of one of the masses using the apparatus provided.
Record V
V = _________________(2 marks)
Explain how you determined the volume V.
b) i) Determine the centre of Gravity of the metre rule and record it.
G ........................................................................................................................... ......................
(1 mark)
(1 mark)
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232/1,232/2,232/3 physics
ii) Arrange the apparatus as shown in the diagram below such that X = 5cm from the pivot with a 100g mass completely
immersed in the solution, hang the other 100g mass from the metre rule and adjust its position until the system is in
equilibrium a shown in the diagram.
X
Y
G
Metre
String
String
String
100g
100g
Saturated(L)
Salt solution
iii) Repeat the procedure above with the following values of X and fill the table.
x (cm)
5
10
15
20
25
30
y(cm)
NB: During each experiment ensure that the position of the pivot does not change.
(c) Plot a graph y (y - axis) against x.
(3 marks)
(d) Determine the slope "s" of the graph.
(2 marks)
(e)Given that S  F Where F is the apparent weight of the mass is the liquid L and W is the actual mass, calculate the value
W
of F and the upthrust U.
(3 marks)
(f) Hence determine the density e of the liquid L.
Question two.
(3 marks)
 A wire mounted on a milliameter scale and labelled X.
 A switch.
 Ammeter
 3 cell holders.
 3 new size D dry cells.
 Seven connecting wires, three with crocodile clips both ends.
 Jockey.
Proceed as follows.
(a) Connect the circuit as shown in the figure below.
Q
Wire X
A
V
S
(b) Adjust the contact Q so that the reading on the voltmeter is 1.3V, note the reading of the current and record it in table below.
(c) Repeat the procedure above for the values of voltage given in the table and record the corresponding values of the current.
(d) Plot a graph of voltage V (y-axis) against current I(A)
(5 marks)
(e) Determine the gradient of the graph.
(3 marks)
(f) State the equation relating the voltage V, the internal resistance r and the e.m.f of the cell.
(2 marks)
(g) From the graph determine the values of
(i) The e.m.f E of the cell.
(1 mark)
(ii) The internal resistance, r of the cell.
(2 marks)
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GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1
MARKING SCHEME
= (main scale reading + thimble scale) - zero error
=
20
6.0  100   0.02mm
 6.0  0.2  0.02
 6.20  0.02
 6.18mm
2. h1p1g = h2p2g ü1
h × 900 = 0.06 × 1200 ü1
3.
Latent heat of fusion
Is the heat required to convert a
substance from solid to liquid state
without change in temperature.
4. Tension
= F = mrw²
= 8 × 0.8 × (2 × 3.14 × 2.5)²
= 15747.536 N
5.
Specific latent heat of fusion
Is the heat required to convert unit
mass /kg of a substance from solid state to
liquid state without change in temperature.
6. In liquids the forces are smaller and molecules are able to roll. over one another while in the gaseous sate, the molecules are
free to more because gases have the weakest force of attraction.
7. (a) In a vacuum.
(b)
Displacement
(m)
Time (s)
8. F = ke
10 = 0.04k
k = 10
0.04
= 250N/m
50 = 250e
e = 50
250
=0.2m
Total e = 0.2  0.2  0.2
3
2
=0.3666m
=36.66cm
9. Silvered glass walls reflect heat away.
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232/1,232/2,232/3 physics
10. A1V1 = A2V2 ü1
× 2² × 3 = × 6² × V2
  22  3
  62
V2 =
 0.33m / s
11. A - Positive terminal.
B - negative terminal
12. C - Powdered carbon and manganese (IV) oxide.
D - Ammonium chloride paste.
13. Liquid A expands and becomes less dense thus reducing the upthrust force in beaker A. Therefore higher uptrhust force in
beaker B. Cause the beam tip towards beaker A.
14.a) Vertical projection
U = 100m/s, g = 10m/s², V=o/s
V² = U² - 2gs
O² = 100² - 2 × 10 × 5
20s = 10,000
s = 500m
b) Horizontal projection
h = ½ g t²
500 = ½ × 10 x t²
t² = √1
= -10s or 10s
= 10s
(c) Range = R = ut
R = 20 × 10
= 200m
(d) Impulse = change in momentum
Ft = (10N × 3S) = 30Ns
= 20N × 2s = 40NS
P = 30Ns - 40Ns
= -10Ns
(e)(i) V  O
, t  (5 ticks  0.01) s
t
= 0.05S
V
 5cm / s 2
0.05
v  0.05  5  0.25cm / s

(ii) V - u = 0.25cm/s
0.125 cm
0.01s
 12 Jcm / s
U 
V - U = DP
V - 12.5 = 0.25
V = 12.5 + 0.25
= 12.75cm/s
L
E
450 N

3
150 N
15.a) (i) M.A 
(ii)
V .R 
No. of teeth on driven gear
No. of teeth on driving gear
80
4
20
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232/1,232/2,232/3 physics
(iii)
n
M .A
 100%
V .R
3
 100%
4
 75%

(b) (i) Converts electrical energy to sound energy.
(ii) Chemical  kinetic  potential
c) Mass of ice = pv
= 0.9g/cm³ × 2000cm²
= 1800g = 1.8kg
Mass of can + ice
= 1.8kg + 0.2 = 2.0kg
Work (w) = f × d = 20N × 5m
= 100j
Power = Work done
time
= 100s = 25J/s or 25 watts
4s
16. a) I.
i) 123 - (70 + 50)
123 - 120 = 3g
ii) Heat gained by water and calorimeter
= mcDq
= 0.07 × 4200 × 25
= 7350J
Heat gained by calorimeter
50
 390  25  487.5J
100
Total heat gained
= 487.5 + 7350 = 7837.5J
II. (i) Heat lost by steam
= ML + MCDE
(ii) = 0.003L + (0.003 × 4200 × 70) = 7837.5S
0.003L = 6955.5
III. Quantity of heat required to melt 1g of ice completely toe water, 334 j of heat is required.
IV. Pure water it has a higher specific heat capacity therefore it takes a lot of heat energy before changing its temperature.
17.(a) A floating body displaces its own weight of fluid.
(b) (i) Volume of B displaced
= 1/3 × 0.012 = 0.004m³
Mass of B displaced
= V = 0.004 × 800 = 3.2 kg
Weight of B = 3.2 × 10 = 32 N
(ii) Weight of liquid A displaced.
= 50 - 32 = 18 N
(iii) Volume of A = 2/3 × 0.012 = 0.008m³
Mass of A =
1
Densities of A
Mass of A
=
Volume of A
1.8kg
0.008 m ³
 225 kgm 3

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232/1,232/2,232/3 physics
c) T = u - mg
=
 34  0.012 800   14  0.012 225  50
 28.75N
(d) (i) To make it float upright.
(ii) To increase sensitivity
18. (a) 2nd The rate of change of momentum of a body is directly proportional to the applied force and takes place in the
direction in which the force acts.
(b) (i)
2
U
d
100

 5m / s  2
20
s
(should be shown on the graph)
ii) S = 20k
iii) When the bench is more rough U reduces hence K reduces when the bench is smooth U, increase hence K increases.
(c) V² = u² + 2as
u + 2 × 1.2 × 400 = 960
V = 30.98 m/s
Momentum = mv
= 800 × 30.98
= 24787.09 kgms-1
mv 2
R  mg 
r
mv 2
200
4²
 mg 

 10
r
1000 1000
 2.133  2 N
 4.133N
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GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2
MARKING SCHEME
1.
M
Eye
I
2.
3.
4.
5.
Rays with arrows in right direction
Object position
Increase the number of turns.
Increase the current in the coil
A - Brown / Red
B - yellow / Green
Fuse - Protect the appliance from excess current.
Image on a plane mirror is virtual while ü1 pinhole forms real / erect in mirror end upside down / on mirror same size as
object while in pinhole the image size varies AORA.
Combined parallel capacitance
C 1  100 F  100 F
 200 F
1
1
1
1
Total capacitance 



CT
200 200 400
1
5

CT
400
C T  80F
From
6.
P  I 2R
75
 .R
75   240
2
R
7.
8.
9.
10.
11.
75  240 2
 768
75 2
Periodic time = 60 secs.
More electrons are released through thermionic ü1 emission hence brightness increases.
In the forward bias majority carriers are electrons. Also barrier p.d. is decreased.
Minimises echoes.
i) Current is produced due to changing flux linking the coil through inductions.
ii) The induced current is such as it produces a magnetic effect opposing the incoming pole.
12.
eye
45°
45°
Image position
Correct rays
13. Yellow, radiowaves, microwaves, Gamma rays.
correct order
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232/1,232/2,232/3 physics
14. (a) (i) Brown lead should be connected where the blue ü1 is, yellow to be connected where the brown is ü1 and the blue lead
to be connected where the green / yellow is connected. (Any two)
(ii) No current will flow.
(iii) The earth pin opens the holes (blinders) for the live and neutral pins. Also to ensure it reaches the metallic part of the
appliance.
(b) i)
60  5  3 1

2
1000
 1.05 Kwh
(ii) = 1.05kwh × 7×6.7 =49.245
15.a)i) Threshold frequency is the minimum frequency below which p.e.e. will not occur. The threshold wavelength is the
maximum wavelength above which p.e.e. will not to be place.
(ii) (I) C = f
3.0 × 108 = 8.0 × 10-7 × fo
fO 
II.
3.0  108
 3.75  1014 Hz
7
8.0  10
E  hf o  12 mv 2
1
2
mv 2  hf  hfo

 6.62  10 34 8.5  1014  3.75  1014
b) (i)
(ii)

 31 .445  10 20 J
12.5  0  10 1  1.25  10 8 Vm
Slope 
20  10  10 7
hc
Slope 
 1.25  10 8
e
6.62  10 34  3.0  10 8
e
1.25  10 8
 15.89  10 18
 1.589  10 19 C
16. (a) E.m.f is the p.d. across the battery in the ü1 open circuit while terminal voltage is the p.d. across the cell is a closed
circuit.
(b) (i) E.m.f = 1.625V ü1 (show unit)
(ii)
E = IR + Ir
V = E - Ir
V = Ir + E
1.5  1.0
0.5

 0.78
0.16  0.8  0.64
r  0.78 
Slope =  r 
(c)
V
S
A
Ammeter in series with cell
Position of voltmeter
d) V = IR = 0.3 × 10 = 3V
P.d. across lamp = 10 - 3 = 7V
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232/1,232/2,232/3 physics
17. (a)
F
F
Point of convergence of rays.
Correct rays, middle ray straight.
b) (i)
U + V (cm)
34.6
32.1
33.3
36.8
40.9
45.4
UV cm²
246
256.5
266
295
327
364
(u  v)
uv
45.4  36.8

364  295
8.6

 0.1246
69
f 
1
 8.02cm
0.1246
(c) Focal length of the eye is variable while that of a camera is fixed.
18. (a) (i) The magnitude of the induced e.m.f is directly proportional to the rate of change of magnetic flux linkage.
(ii) Induction coil use D.C. in the primary circuit while transformer uses A.C in its primary coil.
(b) (i)
NS
VS
NP

VP
8
 4000
2000
 16turns
NP 
(ii)
IP NS

IS NP
4000
 2.0
16
 500 A
(c) (i) As the magnet rotates there is charge in magnetic flux linking the coil. This induces current in the coil hence the bulb
lights.
(ii) Increasing the speed of rotation of the wheels / speeding up.
IP 
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232/1,232/2,232/3 physics
GUCHA SOUTH EVALUATION TEST (GSET) 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 3 (PRACTICAL)
MARKING SCHEME
1. (a) V  r 2 h
A = 1 mark (well labelled)
 2.5   22.5   3.1422
2
S = 1 mark for correct scale
 12.27cm ³
P = 2mks for all pts
b) (i) f1 = 50.0cm
(ii)
X(cm)
5
10
15
Y (cm)
4.0
8.0
12.2
= 1mark - for 4 pts correctly
25
30
plotted.
16.5
20.8
25.0 ±0.5
20
L = 1mark
(c)
(d)
S = 1 mark
P = 2 marks for all pts
A = 1mark if well labelled
L = 1mark for all points correct
plotted and line drawn
Slope S 
F
W
F  S W
S 
y 16.5  4

x
20  5
 100

 0.8333 
 10 
 1000

 0.8333N
 0.8333
W
f
1

0.8333
 1.2 g / cm ³
e
u  1.0  0.8333N
 0.1667
2.
P.d. V (volts)
1.3
1.2
1.1
1
0.9
0.8
0.7
Current I (A)
0.12
1 mark for each value
0.18
0.28
3
0.36
0.42
0.42
±0.1
A = 1 mark (well labelled)
S = 1 mark for correct scale
P = 2mks for all pts
= 1mark - for 4 pts correctly plotted.
L = 1mark
Page | 231
0.7  1.1  0.4

 1.25
0.6  0.28 0.32
E  IR  Ir
E  V  Ir
V  E  Ir
V  Ir  E
V  Ir  E
232/1,232/2,232/3 physics
g )i ) E  y  intercept
 1.5V ( Accept(1.4  1.6)V
(Total  1mark)
ii ) Internal resitance r  Slope
r  1.25
But IR = V
(Total  2marks)
Page | 232
232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
1. Atomic physics is a branch of physics. State what it deals with.
(1 mark)
2. A parker pen was accidentally dropped into a measuring cylinder containing water. The volume of water moved from initial
level to form the final level as shown below.
5
4
Final level
3
2
Initial level
1
If the mass of the parker pen is 0.012kg, determine its density.
(i) Define a vector quantity.
(1 mark)
(ii) Which of the following quantities are vectors: mass, weight, power, time, density and velocity.
(2 marks)
4. Pressure of a laboratory water tap in a school in Nakuru is 40,000 N/m². Calculate the height of the tank from which the water
is supplied.( density of water = 1g/cm³, g=10N/kg)
(2 marks)
5. Explain the cause of random motion of smoke particles as observed in Brownian motion experiment using a smoke cell.
(1 mark)
6. When a particular substance at a certain temperature is heated, It expands. When the same substance at the same temperature
is cooled. It also expands
(a) What is the substance.
(1 mark)
(b) What is the temperature.
(1 mark)
6. When a particular substance at a certain temperature is heated, it expands when the same substance at the same temperature is
cooled. It also expands
(a) What is the substance.
(1 mark)
(b) What is the temperature.
(1 mark)
7. (a) Draw a vernier calliper to show a reading of 7.36cm
(1 mark)
(b) What is the micrometer screw gauge reading in the figure shown below.
(1 mark)
3.
11
12
13
14
0
mm
45
8. State and explain why it would be advisable to use hollow bricks in place of normal building stones in countries which
experience winter.
(2 marks)
9. The three springs shown below are identical and of negligible weight. The extension on the system of springs is 20cm.
20N
20N
Determine the constant of each spring.
10. A Planck of negligible weight is kept in a horizontal position by the forces shown in the diagram below.
8N
Y
(2 marks)
2m
6N
Q
(i) Calculate the magnitude of force Q.
(ii) Calculate the value of Y.
11. Air is blown over a piece of paper as shown below. State what is observed.
(1 mark)
(2 marks)
Piece of paper held horizontal here
Air blown
horizontally
Piece
of paper
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232/1,232/2,232/3 physics
12. The figure represents the velocity-time graph for a lift in a department store. Use the graph to calculate
Velocity
(m/s) 5
1
2
3
4
5
6
7
8
9
Time (s)
(i) The acceleration of the lift.
(1 mark)
(ii) The total distance travelled by the lift.
(1 mark)
4
13. A bicycle tyre is found to have a pressure of 8 × 10 N/m² at 20°C. Assuming that the volume of the air inside remains
constant, calculate the pressure if the temperature of the tyres rises to 29°C when the tyre is left in the sun for sometime,
given that the atmospheric pressure is 105N/m²
(2 marks)
14. (a)An object which is moving over a horizontal surface slows down until the motion finally gets to zero. Explain what is
responsible for this observation.
(1 mark)
(b) A trolley of mass 5.00 kg rests at a plain horizontal shown below.
(i) Show on the sketch, the forces acting on it when pulled in one direction.
(4 marks)
(ii) When the trolley is pulled with a horizontal force of 24N, the trolley accelerates at 3m/s². Find the frictional force
acting on the trolley.
(2 marks)
(c) An automobile of mass 500 kilograms is accelerated from rest along a horizontal surface. The force produced by the engine
is 300N and that due to friction is 50N. What is the accelerated force and what is the acceleration produced?
(2 marks)
15. (a) State the energy changes that occur when
(i) A man climbs a mountain.
(1 mark)
(ii) A woman addresses a crowd using a microphone.
(1 mark)
(b) A machine with a wheel of diameter 1.6m and axle of diameter 0.4m lifts a load of mass 12kg with an effort of 120N.
Given that the acceleration due to gravity is 10m/s².
Calculate
(i) The velocity ratio of the machine.
(2 marks)
(ii) The mechanical advantage of the machine.
(2 marks)
(iii) The efficiency of the machine.
(2 marks)
(c) A bullet of mass 8 × 10-³ kg is fired horizontally into a block of wood of mass 0.6kg which it knocks and moves with an
initial speed of 6m/s. Calculate
(i) The speed of the bullet.
(2 marks)
(ii) The kinetic energy lost in the impact.
(2 marks)
16. (a) Define the term specific heat capacity of a substance.
(1 mark)
(b) In an experiment to determine the specific latent heat of vaporisation of water, stream at 100°C was passed into water
contained in a well lagged copper calorimeter.
The following measurements were obtained.
Mass of calorimeter = 52g
Initial mass of water = 72g
Initial temperature of water = 6°C
Final mass of water + calorimeter + condensed steam = 127g
Final temperature of mixture = 34°C
(Specific heat capacity of water = 4200J/kgk)
(Specific heat capacity of copper = 390J/kgk)
Determine
(i) Mass of condensed steam.
(2 marks)
(ii) Heat gained by water and calorimeter.
(2 marks)
(iii) Given that LV is the specific latent heat of vaporization of steam, write an expression for the heat out by steam.
(1 mark)
(iv) Determine the value of L.
(2 marks)
17.A car runs at a constant speed of 15m/s for 300s and then accelerates uniformly to a speed of 25mls over a period of 20s.
This speed is maintained for 300s before the car is brought to rest with uniform deceleration in 30s.
(i) Draw a velocity-time graph to represent the journey described above.
(3 marks)
From the graph above
(ii) find the acceleration while the velocity changes from 15m/s to 25m/s
(iii) the total distance travelled in the time described.
(iv) the average speed over the time described.
(2 marks)
(2 marks)
(1 mark)
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232/1,232/2,232/3 physics
18. (a) State the Archimedes principles.
(1 mark)
(b) A rubber envelope of a hydrogen filled balloon having volume of 2m³ is held in position by a vertical string as shown
below.
Balloon
Hydrogen gas
String
The mass of the balloon is 1.3kg. Given that density of hydrogen is 0.1kg/m³ density of air is 1.3kg/m³. Find
(i) total weight of the balloon including the hydrogen gas.
(2 marks)
(ii) the upthrust.
(2 marks)
(iii) the tension in the string.
(2 marks)
(c) A solid weighs 50N in air and 44N when complete immersed in water. Calculate
(i) relative density of the solid.
(2 marks)
(ii) density of the solid.
(2 marks)
19. (a) A stone of mass 450g is rotated in a vertical circle at 3 revolutions per second. If the string has a length of 1.5m, determine:
(i) the linear velocity.
(3 marks)
(ii) the tension of the string at positions A and B.
(4 marks)
A
B
(b) State two factors affecting centripetal force.
(2 marks)
Page | 235
232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
1. The figure below shows a flask filled with coloured water. The rubber cork is pushed in until the water rises a short distance in
the glass tube.
Glass tube
Water level
Cork
Coloured water
Heat
When the flask is cooled, it is noted that the level of water first rises before it starts to drop. Explain this observation.
(1 mark)
2. The receiving part of a TV aerial should have a length equal to half the wavelength of the incoming waves.
What is the ideal
8
aerial length for reception of TV transmission of frequency 400MHz. (Speed of radio waves = 3 × 10 m/s)
(3 marks)
3. An uncharged metal rod brought close but not touching the cap of a charged electroscope causes a decrease in the divergence
of the leaf. Explain.
(1 mark)
4. Using the components symbols shown in the figure 1, sketch a series circuit diagram for a forward biased diode.
5. Explain how polarization reduce current in a simple cell.
6. The figure below shows two magnets being used to strike a steel bar.
(1 mark)
Magnet
P
N
Q
S
S
N
Steel bar
Identify he method of making magnets represented by the diagram.
7. The figure shows an electromagnet. State the polarities at X and Y.
X
(1 mark)
(2 marks)
Y
8. Explain how the intensity of X-rays in an X-ray tube can be controlled.
(1 mark)
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232/1,232/2,232/3 physics
9. The figure which is drawn to scale 1 : 5, represents an object O and its image I formed by a concave mirror.
(i) By drawing suitable rays, locate the mark on the figure the position of the principal focus F of the mirror. (3 marks)
10. State the two conditions for total internal reflection in a triangular glass prism.
(2 marks)
11. The graph in figure shown was obtained on a cathode ray oscilloscope (CRO) screen when the output of an a.c. generator
was connected to the input of the CRO. The time-base calibration of the CRO was set at 20 milliseconds per centimetre and
the y-gain at 5 volts centimetre.
Determine the frequency of the voltage.
(2 marks)
12. Pendulum A and pendulum B are freely suspended between the poles of identical magnets. Pendulum A is made of thick
copper plate while B is made a copper plate with slots.
A
B
Pendulum
Copper plate
with slots
Thick copper
plate
N
S
N
S
Pole pieces
Displacement (m)
When the two are set to swing, it is observed that A slows down faster than B. Explain this observation.
13. Arrange the following radiations in order of their increasing energy.
Gamma rays, Infrared, UV, X-rays, white light
14. Water waves are produced in a ripple tank. The following is an example of the wave from that was observed.
0.02
0.04
0.08
0.1
time (s)
(a) (i) From the graph determine the frequency of the wave.
(2 marks)
(ii) Derive an equation relating velocity of a wave, frequency and wavelength.
(2 marks)
(b)Ultrasound scanning can be used by doctors to obtain information about internal structure of human body without the need
of surgery. Pulses of ultrasound are sent into the body from the transmitter placed on the skin.
(i) The ultrasound used has a frequency of 4.5MHz. State why waves of this frequency are called ultrasound. (1
mark)
(ii) A pulse of ultrasound enters the body and its reflection returns to the transmitter after a total time
of 1.6×10 -4S. Calculate
-1
how far the reflecting surface is given that the average speed of ultrasound in a body = 1500ms
(3 marks)
Page | 237
232/1,232/2,232/3 physics
(iii) State why the ultrasound sources are transmitted in pulses.
(1 mark)
15. a)An object O placed in front of a converging lens L O forms an image I on the other side of the lens. Another converting lens
Le is placed such that the two lenses form a compound microscope.
(i) Draw a reason of the set up and sketch the rays to show how the final image is formed.
(5 marks)
(ii) What is meant by virtual image?
(1 mark)
(iii) A lens forms a clear image on a screen when the distance between the screen and the object is 80cm. If the image is 3
times the height of the object, determine. The distance of the image from the lens.
(2 marks)
16. (a)The figure shows the charged plates of a parallel plate air capacitor when the distance of separation is d.
Area = A
Air
d
Area = A
Complete the diagram to show the electric field pattern in the space between the plates.
(1 mark)
(b) Without changing the area of overlap, suggest two methods by which you would increase the capacitance of a capacitor.
(2 marks)
(c) Three capacitors A, B and C are connected as shown in the figure.
8 F
4 F
6 F
90v
Calculate
(i) the charges on each capacitor.
(3 marks)
(ii) the potential difference across each capacitor
(3 marks)
17. (a) (i) State the Lenz's law.
(2 marks)
(b) The transformer has two outputs labelled A and B on the right hand diagram. Complete the table below to show number of
turns and output voltage of each coil.
A
Secondary
Coil
Primary
coil
B
Core
Input voltage
Primary turns Secondary turns
230v
5000
2500
230v
5000
5000
A on B
Output voltage
(c)In a laundry four electric irons each rated 750W, 240V are connected to the 240V mains supply using a 13A fuse.
(i)Can the 13A fuse be suitable for the circuit when all the electric ions are being used (support your answer) (2 marks)
(ii)Calculate the cost of using all the electric ions everyday for 3 hours. If the cost of electricity is shs 15.00 pre kilowatt
hour.
(2 marks)
18. In an experiment involving photo electric emission from a metal surface the following readings were obtained.
Stopping voltage Vs / v
0.2
0.6
1.0
1.8
2.2
Frequency f/1014Hz
8.0
9.0
10.0
12.0
13.0
(a)Explain how you would change the frequency of the incident radiation, without changing the source of radiation. (1 mark)
(b) Plot a graph of slopping voltages, V S, (y-axis) against frequency, f,
(5 marks)
c) Use Einstein's equation of photoelectric effect, namely hf = hfo + ev S and your graph in part (b) to determine a value for
(i) Planck's constant.
(3 marks)
(ii) Work function of the metal.
(2 marks)
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232/1,232/2,232/3 physics
19. a) The diagram below shows the path taken by three radiations X, Y and Z from a radioactive source, through an electric
field.
(+)
Z
Y
(-ve)
X
(i) Identify X, Y and Z.
(3 marks)
(ii) Give a reason for the differences in deviation shown by X and Z.
(1 mark)
b)A radioactive source infront of a Geiger-muller tube shows a high count rate. The count rates are then taken from the source
after placing a thin paper, then a thin aluminium foil and finally a thick lead slab, one at a time between the source and the G
- M tube. It was observed that the paper had no effect on the count rate, aluminium had a small effect while the count rate
(i) Give reasons for the three observations.
(2 marks)
(ii) Deduce the possible radiations from the source.
(2 marks)
(iii) State any two applications for the radiations entitled.
(2 marks)
Page | 239
232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
CONFIDENTIAL INSTRUCTIONS TO SCHOOLS
Question 1
PART A
- A source of heat.
- A cotton thread 50cm long.
- A thermometer
- A complete retort stand.
- 100ml measuring cylinder.
- A calorimeter with a stirrer (N.B teachers are advised to improvise 200ml beaker.
- Some water
- A 100g mass
- A weighing balance (Accuracy 0.1g) to be shared.
PART B
- Concave mirror (focal length 20 cm) and a holder.
- Metre rule
- White screen.
Question 2
Part A
- Retort stand
- Cork
- Optical pin or 2 inch nail.
- Stop watch
- Half metre rule
- Knife edge
- rectangular wooden plank (50cm × 5 cm × 0.5cm) with drilled holes 1, 2, 3, 4, 5, 6
- (3 cm intervals from 25cm mark)
- Sharp pointed object e.g. 2 inch nail
Part B
- A voltmeter (0 - 3 or 0 - 5V)
- An ammeter (0 - 1A)
- A switch
- One dry cell and a cell holder
- Six connecting wires.
- Resistor (10 W)
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
1
.
PART A
You are provided with the following:
 A 200ml beaker.
 A thermometer.
 A complete retort stand.
 100ml measuring cylinder.
 A calorimeter with a stirrer.
 Some water.
 A heat source
 A 100g mass
 A balance
Page | 240
232/1,232/2,232/3 physics
Proceed as follows:
a) Fill the 200ml beaker to about half its volume with water. Clamp the thermometer and lower it into the water, ensuring that its
bulb does not touch the base or sides of the beaker. Tie the 100g mass with the thread securely and greatly lower it into the
water as shown below;
Thermometer
Beaker
water
Stand
100g
mass
Tripod
stand
Heat
b) Weigh the mass of the empty calorimeter and record it.
Mass (MC) = ............................................................................ g
(½ mark)
c) Measure 90 ml of water and gently transfer it into the calorimeter. Measure and record the temperature of the water in the
calorimeter.
q1 = ............................................................................................°C
(½ mark)
d) Determine the mass of water in the calorimeter by weighing both the water and the calorimeter.
MW = ...............................................................................................g
(1 mark)
e) When the water with the 100g mass has started to boiling note and record the temperature q S of the solid.
qs = ....................................................................................................°C
f) Quickly transfer the hot solid into the water in the calorimeter and cover it. Ensure that the calorimeter is well lagged. Stir
gently and note the final steady temperature of the mixture.
q2 = .................................................................................................°C
(½ mark)
g) Given that
Where:
MS = mass of the solid.
MC = mass of the calorimeter
MW = mass of water in the calorimeter
CW = specific heat capacity of water = 4200j/kg/k
CC = specific heat capacity of the calorimeter = 400j/kg
Find the value of Cs the specific heat capacity of the solid.
(2 marks)
PART B
You are provided with the following apparatus:
 Concave mirror and a holder.
 Metre rule
 White screen
a) i) Determine the focal length of the mirror by focusing a distant object.
(1 mark)
ii) Arrange the apparatus as shown in the figure 2 below.
Concave mirror
Screen
Candle
l
fo
x
iii) Place the candle at a distance fo + l (say fo + 2cm) from the mirror.
iv) Starting with the screen at a distance of 100cm from the mirror, gently move it towards the mirror until a sharp inverted
image is formed.
v) Measure and record the distance x,
vi) Repeat step (iii - v) for the other values of L and record your results in table 2. Complete the table.
(4 marks)
b) Plot a graph of x against
(5 marks)
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232/1,232/2,232/3 physics
c) Find the slope S of the graph.
d) Given that
(3 marks)
f
x   k determine f from your graph.
L
(2 marks)
2. a) You are provided with the following :PART A
 Retort stand.
 Cork
 Optical pin on which the wooden plank is suspended
 Stop watch
 Half-metre rule
 Knife-edge.
 Rectangular wooden plank (50cm × 5cm × 0.5cm)
(b) (i)Take, the hardboard and using the knife-edge, determine the position of the centre of gravity. Mark this as G.
(ii) Measure and record the distance L of each of the holes from G. ie G to hole 1, G to hole 2 etc.
(iii) Set the apparatus as shown in the diagram above.
Cork
Optical pin
6
5
4
3
2
1
Stand
G
wooden plank
(iv) Displace the wooden plank through a small angle q and release it to oscillate. Determine time t for 10 oscillations and fill
in the results in table 2
(v) Repeat step (vi) with the pin in the holes 2, 3, 4, 5 and 6 and complete the table of results.
Hole
1
2
3
4
5
6
Distance L (cm)
Time t for 10 oscillations
Periodic time T(s)
T²(Sec)²
T²L(m sec²)
L²(m)²








(d) Plot a graph of T²L on y (axis) against L²
(d) Determine the gradient of you graph.
(e) Given that the equation of the graph your have plotted is:
f) From the graph determine the values of g and k.
PART B
You are provided with the following.
A voltmeter
Resistor (100W)
A switch
Ammeter
Dry cell
Cell holder
A switch
six connecting wires
(5 marks)
(2 marks)
(2 marks)
Page | 242
232/1,232/2,232/3 physics
i) Connect the above apparatus as shown in the circuit diagram below with the switch S open.
100
ii) With the switch S open record E the voltmeter reading.
iii) Close the switch and record V, the voltmeter reading and I, the ammeter reading.
V=........................................................................................................................... .............
I=..........................................................................................................................................
iv Given that:
E - V = Ir
Find r for the dry cell.
(1 mark)
(1 mark)
(1 mark)
(1 mark)
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232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
MARKING SCHEME
1. Its the study the particles consisting the nucleus of atoms and Energy changes involved or Involves the study of the structure
of the atom and its energy states.
2. Volume of stone = 4.00 - 2.00
= 2.00cm³

m
0.012

 6000kg / m 3or 6 g / cm 3
v 2  106
3. i) Vector quantity is a quantity having both magnitude (size) and direction.
ii) Weight and velocity
4. p = hpg
40,000 = h × 1000 × 10
h = 40,000
10,000
= 4m
5. They move in continuous random movement because of uneven bombardment by the invisible particles or molecules of the
air.
6. a) water
b) 4°C
7. a)
7
8
5
14.97 mm
8. Hollow bricks contain air in them, which is a poor conductor hence reduces heat loss.
9. F = ke
e1 + e2 = 20cm
10 20

 20
k
k
10  20  20k
20k  30
k  1.5 N / cm or 150 N / m
10. i)
Sum of Upward forces = sum of Downward forces
8N = 6N + Q
Q= 8-6
Q = 2N
ii) Clockwise moments = Anticlockwise moments.
2 y  26
26
y
2
 6m
11. Paper rises / is lifted.
12. (i) Acceleration  5  0
Deceleration
 2.5m / s 2
20
05

 1.25m / s 2
73
Page | 244
ii)
Distance
  2  5  3  2   5   7  3  5
1
2
232/1,232/2,232/3 physics
1
2
 5  5  10
 20m
13.
P1  8  10 4  1  105
 8  10  10 4
 18  10 4
 1.8  105
T 1 273  29  302
T2  273  20  293
P1 P2

T1 T2
P2
1.8  105

302
293
1.8  105  302
P2 
293
 1.855  105 Pa
14.(a) The object decelerates due to frictional force between the object and the surface. Frictional force acts to oppose the
motion between the object and the surface.
Reaction ®
(b) (i)
(normal to surface of the trolley)
Or
Applied force
Frictional forces (f)
Weight of trolley
ii) Acceleration - unbalanced force = ma
Applied force - friction force = ma
24 - F = 5.00 × 3
F = 9.0N
(c) Acceleration = applied force - frictional force
= 300 - 50 = 250N
F = ma
250 = 500 a
a = 0.5m/s² ü1
15. (a) i) Chemical  kinetic  potential
ii) Chemical  sound electrical  sound
(b) i) V.R =
2R R 0.8
 
4
2r
r 0.2
ii) M.A  Load  12kg  10m / s  1.0
2
Effort
iii) Efficiency =
120N
M .A
1
 100   100
V .R
4
 25%
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232/1,232/2,232/3 physics
c) (i) Momentum before impact = momentum after impact.
m1u1  m2u 2  m1v1  m2 v2

8  10 3  u1  0  8  10 3 v  0.6  v

8  10 3 u1  0.608  6
0.608  6
8  10 3
 456m / s
u1 
ii) K.E before impact =
 12  8  103  4562  831.744J
 12  0.608  6 2  10.944 J
831.744  10.944J
K.E after impact
K.E lost =
 820.8 Joules
16.a) Specific heat capacity of a substance is the quantity of heat required to raise the temperature of a unit mass (1kg) of a
substance by 1k.
b) i) Mass of condensed steam
= 127 - (52 + 72)
= 3g
ii) Heat gained by water
= 30 × 4200 × 28
1000
= 3528 Joules
Heat gained by calorimeter
Total = 3528J + 567.84J
= 4095.84J
iii) Heat given out by steam
0.003L + 0.003 × 4200 × 66
0.003L + 831.6
iv) Total heat gained = Total heat given out by steam
4095.84 = 0.003L + 831.6
3264.24 = 0.003L
L = 1088080
= 1.088 × 106 J/kgK.
17. (i)
Velocity
(m/s) 25
20
15
10
5
0
200
(ii) Acceleration
20
.
(iii) Distance
400
600
25  15   10  0.5m / s 2

800
Time (s)
20
 15  300  4500m

1
2
25  15 20  400
 300 25  7500
 12  30  25  375
 12775m
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232/1,232/2,232/3 physics
(iv) Speed
Dis tan ce
time
12775m

630s
 20.28m / s

18. (a) When a body is partially or totally immersed in a fluid it experiences an upthrust equal to weight of fluid displaces.
(b) (i) Weight of hydrogen
 vdg
 2  0.1  10
 2N
Total weight
= Weight of hydrogen + weight of balloon
= 2 + 13 = 15N
ii) Upthrust = weight of displaced air
= vdg
= 2 × 1.3 × 10 = 26N
iii) Tension = U - W
= 26N - 15N = 11N
19. a) i) f  3Hz
  2f
 2  3  6rad / sec
V  r
 1.5  6
 28.278m / s
ii) Alt. A
mv 2
T 
 mg
r
2
0.45  28.278

 0.45  10
1 .5
 239.894  4.5
 235.394N
2
Alt B T  mv  mg
r
 239 .894  4.5
 244 .39 N
Page | 247
232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
MARKING SCHEME
1. The flask contracted first causing the water level to rise. Further cooling causes the water level to drop as water contracts
faster than glass.
1 mark
2. V  f
400mHz  4  108 Hz
3  108  4  108 
3
   100
4
 0.75m
L
3.
1
2
 0.75m  0.375m
Metals get charged by induction, the charges are transferred from the electroscope this causes earthing, / charges on the
electroscope induce opposite charges on the conductor.
1 mark
4.
5.
Sets up aback emf
hydrogen insulates the electrode.
6. A = North
B = South
7. X = North
Y = South
2 marks
8. Increasing / decreasing filament current.
1 mark
1 mark
9.
3 marks
I
10.i) The ray of light must be from more optically dense medium to a less dense medium.
ii) The angle of incidence must be greater than the critical angle.
11.
2 marks
T  160ms
F
1 1000

 6.25Hz
T
160
12. When the conductors move in a magnetic field, eddy currents are produced. The eddy currents produced a force that oppose
their motion. The eddy currents in A are more than in B since slots reduce the eddy currents.
13. Infrared, white light, UV, X-rays, gamma rays.
14. a) i)
T = 0.06Sec
F = 1/T = 16.7 Hz
2 marks
ii) Velocity = displacement (l) / Time (T),
Frequency = 1 / period (T(
hence, V = fl
2 marks
b) i) They are above 20kHZ audible sound
1 mark
Page | 248
232/1,232/2,232/3 physics
ii)
 V t
3 marks
1500  0.8  10 4 s
 0.12 m
iii) One pulse must return before the second one is sent.
15. i)a)
lo
1 mark
le
eye
Fe
Ie
Io Fo
ii) Image formed by apparent intersection of light of light rays. or images that cannot be formed on the screen. 1 mark
b) (i) They are above 20KHZ audible sounds.
ii)
distance = 1500 × 1.6 × 10-4
2
= 0.12m
16.a)
b) Decrease the distance (d) between plates introduce / change the dielectric material e.g. polythene, glass.
c) CAB = CA + CB
= 8mF + 6mF
= 14mF
Total charge, Q = VC
= 90 × 3.11mF
= 279.9 or 280 mC
Charge on C = 280mC
P.d on
Q
280C
V 
T
C

4F
 70volts
(90 - 70) = 20 volts
P.d. on (A + B)
=
QA = CA × V = 8mF × 20 = 160mc
QB = CB × V = 6mF × 20 = 120mc
i) P.d VC = 280mc
4
= 70mc
P.d. (VA) = 20 volts
P (VB) = 200 volts
17. a) i) Lenz's law: the induced current is always such that it opposes the change of magnetic flux which produces it.
ii)The magnitude of the induced emf in a is directly proportional to the rate of change of magnetic flux.
b)
Secondary
A
Output voltage
2500
A
115V
5000
B
230V
c) i) Maximum current drawn.
ii) Yes, tie the 13A fuse is suitable.
iii) Energy = 750 × 4 × 3 hrs
Units = 9kwh
Cost = 9 × Shs 15
= shs 35
Page | 249
232/1,232/2,232/3 physics
18. a) By using different colour fillers.
b)
c) hf = hfo + evs
evS = hf - hfo
h
 0.4  10 14
e
h  0.4  10 14  e
m
 6.4  10 34 Js
19. a) i) X = alpha
Y = Gamma
Z = Beta
ii) Beta particles are lighter - thus gives maximum deflection.
Alpha particles are heavier thus gives slight deflection.
b) i) Paper - there were no alpha radiations from the source. Thin aluminium foil - There were beta radiations since the
count rate was reduced.
iii) Radiation therapy, detecting of faults in pipes etc.
Page | 250
232/1,232/2,232/3 physics
WESTLANDS JOINT EXAMINATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (;PRACTICAL)
MARKING SCHEME
1. PART A
b) MC = 60g ü½ (work with the students value)
c) q1 = 27 ± 1°C ü½
d) Mw = 90g ü1
e) q2 = 98°C or 100°C ü½
f) q2 = 34°C ± 1°C ü½
0.06  400 7  0.09  4200  7 
g)
CS 
0.1 66
2814

66
 426.36 J / kgk
PART B
L (cm)
2
3
4
5
6
7
8
9
X (cm)
-
-
-
-
-
-
-
-
½
½
½
½
½
d)
x


½
½
½
(triangle must be shown on the graph)
f
k
L
is the gradient Hence f = slope
Slope from the graph
2.
Hole
1
2
3
4
5
6
1
Distance L (cm)
Time t for 10 oscillations
2
1
2
1
1
Periodic time T(s)
T²(Sec)²
T²L(m sec²)
L²(m)²
c)
Graph
Axes - 1
Scale - 1
Plotting - 2
Line - 1/5
d) Slope = DT²L
L²
slope = 4p² ; g = 4p²
g
slope
3 marks
Page | 251
232/1,232/2,232/3 physics
e) Intercept
4 ²
 k²
g
Intercept
k² 
Slope

k 
PART B
E = 1.5 ± 0.1V
V = 1.4 ± 0.1V
I = 0.12A ± 0.01A
iv) E - V = Ir
r = 0.1 = 0.83 W
0.12
Intercept
slope
i)
ii)
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KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1 (THEORY)
1. State the name of the instrument used to take the following readings:
i)0.035m
ii) 0.00245m
2. The figures a and b below shows capillary tubes inserted in water and mercury respectively.
(1 mark)
(1 mark)
Capillary
tubes
Mercury
Water
(a)
(b)
It is observed that in water, the Meniscus in the capillary tube is higher than in the beaker, while in mercury, the Meniscus in
the capillary tube is lower than the meniscus in the beaker. Explain these observations.
(2 marks)
3. The barometric height in a town is 65cmHg. Given that the standard atmospheric pressure is 76cmHg and the density of
mercury is 13600 kg/m³, determine the altitude of the town. (Density of air is 1.25kg/m³)
(2 marks)
4. State and explain one way in which vacuum flask is adapted to its function.
(2 marks)
5. The figure below shows a uniform bar of length 1.4m pivoted near one end. The bar is kept in equilibrium by a string as
shown.
20cm
30cm
6.
Given that the weight of the bar is 1.5N, determine the tension in the string.
The figure below shows a pithball being lifted into a funnel end of a blower.
(3 marks)
Air blower
Air blow
Pith ball
Velocity (M/s)
Explain this observation.
(2 marks)
7. A person carrying a heavy luggage using one hand leans away from the luggage. State the reason for this.
(1 mark)
8. Robert Brown introduced some pollen grains on water surface. When he observed the pollen grains under a magnifying glass,
they were seen to move in a constant random motion. Explain the cause of this random motion.
(1 mark)
9. The water level in a burette is 30.6cm³. 50 drops of water each of volume 0.2cm³ are added to the water in the burette. What
is the final reading of the burette?
(2 marks)
10. The graph below is a sketch of a velocity-time graph of a car which was travelling at a constant velocity before the brakes
were applied. Calculate the distance travelled after the brakes were applied.
(3 marks)
20
10
0
5
Time(s)
10
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11. Three identical springs each of spring constant 10Nm-1 and weight 0.5N are used to support a load as shown.
A
B
C
6N
Determine the total extension of the system.
(3 marks)
12. The figure below shows a bimetallic strip in electric circuit made of two metals A and B. B expands more than A.
Y
P
X
Q
A
B
X and Y are metal contact while P and Q are identical bulbs. Explain the effect on the bulb when ice cold water is poured
onto the strip.
(2 marks)
13.(a) State the unit specific latent heat of a substance.
(1 mark)
(b) In an experiment to determine specific heat capacity of liquids, a student used 2.0 kg each of the liquids water glycerine
and paraffin. Each of the liquids was supplied with 21600J of heat energy under the same conditions. The table below
shows the temperature rise for the liquids.
Liquid
Water
Glycerine
Paraffin
Temperature rise (°C)
2.6
4.4
4.9
(i) Suggest a reason for the difference in the rise in temperature.
(1 mark)
(ii) Calculate the specific heat capacity of paraffin.
(3 marks)
(c) 5g of water at 20°C is heated until it boils at 95°C. On further heating, the temperature of the water does not change until
it has all vapourised. Calculate the amount of heat required to convert all the 5g of water to steam, given that the latent
heat of vaporisation of water is 2.26 × 106 J/kg and specific heat capacity of water is 4200J/kg°C
(4 marks)
(d) State one physical property of a good thermometric medium which may be used to measure temperature.
(1 mark)
14. a) What is meant by perfectly inelastic collision.
(1 mark)
b) A minibus of mass 1600 kg travelling at a constant velocity of 20mls collides with a stationary car of mass 800kg. The
impact takes 2 seconds before the two move together and come to rest after 15 seconds.
Determine
i)The common velocity.
(3 marks)
ii) The distance moved after the impact.
(3 marks)
c)A man uses the inclined plane to lift a 50kg load through a vertical line height of 4.0m. The inclined plane makes an angle of
30° with the horizontal. If the efficiency of the inclined plane is 80%, determine
The effort needed to move the load up the inclined plane at a constant velocity.
(3 marks)
15. (a) The figure below shows a set-up that may be used to verify pressure law.
Pressure gauge
Stirrer
Thermometer
Water bath
(i) State the measurements that should be taken in the experiment.
(ii) Explain how the measurements in (i) above may be used to verify pressure law.
(2 marks)
(3 marks)
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(b) A column of air 26cm long is trapped by mercury 5.0cm long as shown in the figure (a) below. When the tube is inverted as in
figure (b) the air column becomes 30cm long. What is the value of atmospheric pressure.
(3 marks)
Air
30cm
5cm
5cm
26cm
a)
b)
c) A steel cylinder capacity 0.5m³ contains nitrogen at a pressure of 30,000 pa when the temperature is 27°C. What will be
the pressure of nitrogen if it is allowed to flow into another cylinder of capacity 9.5m³ with the temperature reduced to -23°C.
(3 marks)
d) State the difference between the temperature measured in Kelvin scale and Celsius scale.
(1 mark)
16. (a) Differentiate between speed and velocity.
(1 mark)
(b) The figure below shows velocity-time graphs for two objects A and B drawn on the same axes.
V(m/s)
A
B
t(s)
State with reason which of the two objects stops in a shorter distance when the same size of force is applied against each
given that they are of equal masses.
(2 marks)
c) An object moving at 26m/s starts to accelerate at 2m/s² so that its velocity becomes 48m/s . Find
(i) The distance moved during this acceleration.
(2 marks)
(ii)The object is now braked so that it comes to rest in a time of 12 seconds. Determine the braking force if its mass was
2700g.
(2 marks)
d) (i)When a planet, orbits the sun, it experiences a centripetal force. State what provides the centripetal force.
(1 mark)
(ii) State the purpose of banking roads at bends.
(1 mark)
( iii)A student whirls a stone of mass 0.2kg tied to a string of length 0.4m in a vertical plane at a constant speed of 2
revolutions per second. (Take acceleration due to gravity g as 10ms -2)
I. State two forces acting on the stone when it is at the highest point.
(2 marks)
II. Determine the angular velocity of the stone.
(2 marks)
17. (a) The figure below shows a rectangular object of mass 100kg tethered to the sea-bed by a wire. The dimension are 4m ×
1.5m × 2m
1.0m
4m
m
1.5
Buoy
Surface of water
Wire
Sea bed
Calculate the:
i) Weight of sea water displaced by the buoy (density of sea water = 1100kgm -3)
(3 marks)
ii) Upward force exerted on the buoy by the water.
(1 mark)
b) A test tube of mass 10g and uniform cross-sectional area 4cm² in partly filled with lead shots and floats vertically in water
with 5cm a its length submerged.
Test tube
5cm
Water
Beaker
Find the :
i) mass of the lead shots (density of water = 1g/cm³)
ii) length of the test-tube that would be submerged in a liquid of density 0.75 gcm-3.
(3 marks)
(2 marks)
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232/1,232/2,232/3 physics
KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2 (THEORY)
1. The diagram below shows two parallel mirrors M 1 and M2 and a ray of light being incident on one of the mirrors as shown.
Trace the ray of light through the mirrors.
(2 marks)
M1
20°
M2
2. A metal disc in slowly brought close to a lightly charged electroscope. State and explain the observation made.
3. The figure below shows a dry cell.
(2 marks)
X
Powdered carbon
+
Manganese (iv) Oxide
Y
Ammonium
Chloride paste
Name the parts X and Y
State the function of the powdered carbon and manganese (IV) oxide.
4. The figure below shows a section of a flexible wire carrying current perpendicularly out of the paper.
A
(2 marks)
B
The wire moves in the direction shown as current passes through it.
i) Label the polarities of the magnets A and B.
(1 mark)
ii) Explain the behaviour of the flexible wire.
(2 marks)
5. Distinguish between x - rays and g - rays based on production.
(1 mark)
6. An electric heater is found to have a resistance of 950W when operating normally on a 240V mains. Determine the power
rating of the heater.
(2 marks)
7. The figure below shows a path of a ray of light through a rectangular block of perspex placed in air.
42.5°
Calculate the refractive index of perspex.
8. The figure below shows two parallel current-carrying conductors A and B through a piece of cardboard.
A
(2 marks)
B
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i) Sketch the magnetic field pattern produced.
(2 marks)
ii) Identify the nature of the force between them
9. The figure below shows two parallel rays incident on a concave mirror. F is the focal point of the mirror.
C
F
Sketch on the same diagram the path of the rays after striking the mirror.
10. The table below shows part of the electro magnetic wave spectrum in order of decreasing wavelength.
A
B
(1 mark)
Infra Red
Visible light
C
(2 marks)
D
i) How are waves C produced
ii) State one use of the wave D.
11. The figure below shows the displacement-time graph for a certain wave.
(1 mark)
(1 mark)
Displacement
8
4
1
2
3
4
5
Time|(s)
4
Determine the frequency of the wave.
(2 marks)
12. (a) State ohm’s law.
(1 mark)
(b)A battery of emf E drives a current of 0.25A when connected to 5.5W resistor. When the 5.5W resistor is replaced with
2.5W resistor, the current flowing becomes 0.5A. Find the emf E and the internal resistance r of the battery.
(4 marks)
c) i) State three factors affecting the capacitance of a parallel plate capacitor.
(3 marks)
ii) The figure below shows a circuit containing two capacitors of 2F and 3F respectively.
Determine the pd across AB given that the total charges in the capacitors is 1 × 10 -4 coulombs.
(3 marks)
d) The audible range of frequency for a certain person is 30Hz to 16580Hz. Determine the largest wavelength of sound in air
the person can detect (Speed of sound in air = 330mls)
(3 marks)
13. (a) The figure below shows part of the lighting circuit of a house.
Live
Neutral
i) Explain why a fuse is included in the circuit.
(1 mark)
ii) Explain why the fuse is placed in the live wire rather than in the neutral wire.
(1 mark)
iii) Each lamp has a power of 60W. Calculate the current through one lamp when it is switched on.
(2 marks)
iv)The fuse has a rating of 4A. Calculate the maximum number of lamps that can be connected and switched on without the
fuse blowing. Each bulb is parallel with the power supply.
(2 marks)
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232/1,232/2,232/3 physics
b) i) The figure below shows a step-up transformer commonly used at a power station.
Input
AC
Output
AC
What is meant by a step-up transformer
ii) Why does a transformer work with AC only?
iv) State two ways in which power is lost in a transformer.
v) Explain why the emf produced at a power station is stepped up.
14.a) Differentiate between thermionic and photoelectric effect.
b)The figure below is a graph of stopping potential V S against frequency in an experiment on photoelectric effect.
(1 mark)
(2 marks)
(2 marks)
(2 marks)
Vs(v)
3.0
2.0
1.0
0
1.0
2.0
14
Frequency (X10 HZ)
-1.0
-2.0
Given that ev = hf - hfO where e is the charge on an electron (e = 1.6 × 10-19 ) Determine
i) the hreshold frequency.
ii) Planck's constant (h)
iii) Work function WO for the metal in Joules.
15. a) In the experiment to observe interference of light waves, a double slit is placed close to the source.
(2 marks)
(4 marks)
(3 marks)
S1
Monochromatic
source
S2
Sreen
Double slit
i) State the function of the double slit.
ii) State and explain what is observed on the screen.
iii) State what is observed on the screen when,
I) the slit separation S1S2 is reduced.
II) White light source is used in place monochromatic source.
b) The figure below shows a set up by a student.
(1 mark)
(3 marks)
(1 mark)
(1 mark)
Electric buzzer
Steam from
boiling water
State and explain what happens to the sound from the buzzer as the bottle and its contents are cooled to 0°C.
(3 marks)
16. a) Distinguish between seal image and a virtual image.
(1 mark)
b)The distance between an upright image and the object produced by a thin lens is 40cm. The image is 3 times as tall as the
object.
i) State the type of lens used.
(1 mark)
ii) Determine the object distance.
(2 marks)
iii) Determine the radius of curvature.
(3 marks)
iv) State one application of the lens as used in question (b) above.
(1 mark)
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232/1,232/2,232/3 physics
KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
CONFIDENTIAL INSTRUCTIONS TO SCHOOLS
Each candidate should be provided with the following:
Question 1
 One metre rule and a half-metre rule
 Two complete stands.
 Three pieces of thread, 1m, 30cm, 30cm
 One optical pin
 One helical spring
 200g mass
 A cellotape (10cm)
 Stop watch
Question 2.
 4 optical pins
 Plain paper
 Protractor
 Some plasticine
 Triangular glass prism (60°)
 3 size D dry cells
 100cm nichrome wire on a mm scale
 A bulb (2.5V) and a bulb holder.
 8 Connecting wires (at least 4 with crocodile clips)
 Cell holder
 A voltmeter (0 - 5.0)V
 An ammeter (0 - 1.0A)
 A Jockey
KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
1. You are provided with the following apparatus
- A metre rule and a half-metre.
- Two complete stands.
- Three pieces of thread (1 metre , 30cm and 30 cm)
- One optical pin
- One helical spring.
- 200g mass
- A cellotape (10cm)
.
Stand
Spring
Stand
metre rule
5cm
L cm
5cm
Pointer
200g
Bench
b) i) Fix the optical pin using the cellotape at one end of the metre-rule to act as a pointer.
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ii) Suspend one end of the metre rule with a thread at 5cm mark from the end.
iii)Suspend the other end of the metre rule with spring also 5cm from the other end so that the metre rule is horizontal.
iv)Hold the half-metre rule vertically on the bench so that it is near the end with a pointer as shown in the figure above.
c) i) Read the pointer position LO = ................................................. cm
(1 mark)
ii) Hang on the horizontal metre rule the 200g mass at a length L = 10cm from the spring
iii) Record the extension, e, of the spring in table 1 below.
iv) Displace the mass slightly downwards and release it to oscillate vertically, time for 20 oscillations.
v) Record in the table 1 the time for 20 oscillations
vi) Repeat steps c(ii), (iii), (iv) and (v) for the other positions L, of the mass.
(8 marks)
Table 1
Length L (cm)
10
20
30
40
50
Extension e, cm
Time for 20 oscillations
Periodic time T (S)
T²(S²)
d) Plot the graph of extension , e against T² on the grid provided.
e) Calculate the slope, s of the graph.
f) Given that
2
(5 marks)
(3 marks)
Determine the value of P
2. a) PART A
You are provided with the following
- 4 optical pins and plain paper.
- Protractor
- Soft board
- Some plasticine
- Triangular glass prism.
i) Set up the apparatus as shown below.
(2 marks)
e
PT
c
4 2
M
plastacine
A
Q
P2
P1
D
T
Incident ray
P3
P4
L
N
ii) Measure angle A of the prism using protractor.
(1 mark)
A = ...........................................................................
iii)- Place the prism on a plain paper and trace its outline with a pencil.
- Attach some plasticine to the prism to indicate the refracting angle A.
- Construct a normal at point T along LM
- Draw an incident ray to strike the prism at T at 60°
- Replace the prism and press pins P 1 and P2 to define the incident ray.
- View the pins P1 and P2 from the opposite face MN. Insert Pins P3 and P4 so that they appear to be in line with the images of P 1
and P2. Remove the prism and join P3 to P4 to give emergent ray.
- Extrapolate the emergent ray into the prism so as to meet the extrapolated incident ray at Q.
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- NB- Sheet of paper with drawing most be handed in with this question paper. Ensure you write your name.
iv) Measure angle D
D = ...........................................................
Given that 1  90   A  D  and
A
2 
 2 
v) Find q1 and q2
2
q1 = ............................................................................
q2 = ............................................................................
vi) Find n given that
n = ..............................................................................
2. b) You are provided with the following apparatus.
- 3 size D dry cells.
- 100cm nichrome wire on a mm scale
- A Bulb (2.5V) and a bulb holder.
- 8 connecting wires (at least 4 with crocodile clips)
- Cell holder
- A voltmeter (0 - 5V)
- An ammeter (0 - 1A)
- A Jockey
a) Connect the apparatus provided as shown in the diagram below.
(1 mark)

(1 mark)
(1 mark)
(2 marks)
S
L
x
P
100cm mark
mm scale
Nichrome wire
Jockey
A
Bulb
V
Procedure
b) Place the jockey at x = 20 cm from P, then close the switch.
c) Repeat the experiment by placing the jockey at X=40, 60, 70 and 80cm from P
Length L (cm)
20
40
60
(6 marks)
70
80
I (A)
V (v)
Log I
Log V
d) i) Plot a graph of log I against log V on the axes provided.
(3 marks)
ii) Determine the slope, s, of the graph.
(2 marks)
iii) The relationship between current I (A) and p.d, v (v) is given by the equation I = kv n where k and n are constants of the
bulb.
The equation reduces to log I = n log v + log k.
Determine using your graph the value of k and n
(2 marks)
Page | 261
232/1,232/2,232/3 physics
KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1
MARKING SCHEME
1. (i) Metre rule
(ii) Micrometer - screw gauge.
2. In (a) the adhesive force between water molecules and glass molecules is stronger than cohesive force between water
molecules while in (b) the cohesive forces between mercury molecules is stronger than adhesive force between mercury and
glass molecules.
3. P  heg
0.76  0.65   13600  10
 1.25  10  h
h  1,196 .8m
4. - Presence of a vacuum - prevents heat losses by conduction and convection.
- Shiny / silvery glass surface - prevents heat loss by radiation
- Plastic lid / cork - prevents heat loss by evaporation.
5.
30cm
50cm
40cm
20cm
1.5N
Clockwise moments = Anticlockwise moments.
(0.7 × 1.5) = (1.2 × T)
1.05 = 1.2T
T = 0.875N
6. The blown air moves at the highest velocity there by reducing the pressure above the funnel, the greater atmospheric pressure
below pushes the pithball up the funnel.
7. To shift the centre of gravity / adjust COG / maintain equilibrium / restore balance.
8. Random motion is due to collision between invisible molecules of water moving in constant random motion and pollen
grains.
9. 30.6 - (50 × 0.2)
= 20.6cm³
10. Distance covered = area of the triangle
= ½ × 5 × 20
= 50m
11. Extension of A
Extension of B and C
Total Extension = 0.7 + 0.3 = 1.0 m
12. Bulb P lights, metal B contracts more than A, thereby making contacts with metal y.
13.(a) J / kg C° or Jkg-1k-1
(b) (i) Difference in heat capacities.
(ii) MC = 21600
2 × C × 4.9 = 21600
C = 21600
2 × 4.9
C=2204.08Jkg-1k-1
c) Q = MC + mLv
= (0.005 × 4200 ×(95 - 20) + (0.005 × 2.26 × 106)
= 12,875 J
d) - Expand and contract uniformly.
- Clearly visible
- Not stick on side of glass
- Have wide range of temperature.
14. (a) - Perfect collision both momentum and energy is conserved.
-Or two separate after impact
b) m1u1 + m2u2 = (m1 + m1)v
(1600 × 20) + (800 × 0) = (1600 + 800)v
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32000
= 2400v
v
= 13.33 m/s
ii) v = u + at
= 13.33 + 15a
a = -0.89 m/s²
v² = u² + 2as
c)
v 2  u 2 0  13.33

2a
 20.89
 99.83m
1
1
VR 

2
Sin 30 0.5
MA
Eff
100  MA 
 VR
VR
100
80
MA 
 2  1.6
100
Eff 
MA
L
L
E
E
MA
50  10
E
1.6
 312.5 N

15.a) (i) Measure values of pressure ü and temperature
(ii) Temperature varies with pressure.
 Values of temperature and their corresponding values of pressure are recorded.
 A graph of pressure against temp is plotted.
 The graph obtained is a straight line curve showing that pressure is directly proportional to temperature.
b) P1V1 = P2V2
26 × (a + 5) = 30 (a - 5)
26a + 130 = 30a - 150
4a = 280
a = 70cmHg
Gas pressure
= Atm P + Heg
P 1V 1 = P 2V 2
(x + 5) 0.26 = (x - 5) 0.30
x
c)
2.8
 70 cmHg
0.04
P1V1
PV
 2 2
T1
T2
P  9.5
30,000  0.5
 2
300
250
P2  1315.79Pa
d) Kelvin scale starts at absolute zero while Celsius scale starts at 273K
16.a) Speed is the distance covered per unit time while velocity is the displacement covered per unit time.
b) Object B
Reason: Its acceleration is more than that of A (due to high gradient of velocity - time graph)
c)
i) V 2  U 2  2as
48²  26²  2  2s
S  407m
OR
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S  ut  ½ at and V  u  at
S  26  11  ½  2  11²
S  407 m
ii) F = Ma or F =
M (v  u )
t
2.7  0  48 

12
 10.8 N
d)
i) Gravitational force (between the planet and the sun)
ii)- Increases the centripetal force acting on the body /
Prevent skidding / toppling / rolling / overturning.
Enable higher (critical) speed.
iii) I)- Weight / force of gravity
- Tension
II) w = 2pf = (2 ×2p)
OR
w
2
T

2
0. 5
17.a) i) W = upthrust = Veg
= (4 × 1.5 × 1) × 1100 × 1
= 66,000 N ü1
ii)Upwards force = upthrust = 66,000 N
iii) T + W = U
T + 1000 = 66000
T = 65000 N
b) i)Weight of lead shots + weight of test tube
= weight of fluid displaced.
Weight of lead shots + 0.1
=
(5 × 4 × 10) × 1000 × 10-6)
Weight of lead shots = 0.1N
Mass of lead shots = 10g
ii) Weight of fluid displaced = 0.2 N
 0.2 
5
3
V 
  2.66 10 m
 7500 
V × 750 × 10 = 0.2 N
Length of test tube
=
 2.66 105 

  0.066M
4
 4 10

or 6.66cm
Page | 264
232/1,232/2,232/3 physics
KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/2
PHYSICS
PAPER 2
MARKING SCHEME
1.
20°
20°
70° 70°
20°
70° 70°
20°
2. The leaf divergence decreases
The disc is induced with an opposite charge, which attracts. the charge in the electroscope causing leaf divergence to
decrease.
3. X - carbon Rod (positive plate)
Y - Zinc container (Negative plate)
Powdered charcoal - increase the surface area of the carbon rod.
Manganese (IV) oxide is a depolariser.
4. A - North pole
B - South pole
It moves upwards, due to the interaction the magnetic fields of the current - carrying conductor and the magnets to produce
the force.
5. X - rays are produced when very fast moving electrons are suddenly stopped while g - rays are produced from the nuclei of
6. P = V²
R
240  240
950
 60.63W

7.
1
Sinc
1

Sin 42.5
 1.48
n
8.
Force - attraction
9.
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232/1,232/2,232/3 physics
10. (i) Produced by very hot bodies e.g. arcs sparks.
OR
- Produced in mercury vapour lamps.
11. Period T = 2 seconds
1 1

T 2
 0.5Hz
f 
12.(a) The current flowing through a conductor is directly proportional the potential difference applied between its ends provided
the temperature and other physical conditions are constants.
b) (i) E = IR + Ir
E = 0.25 × 5.5 + 0.25 r
E = 0.5 × 2.5+ 0.5 × 5
E = 1.35 + 0.25r
E = 1.25 + 0.5 r
0 = 0.10 - 0.25 r
 0.25r = 0.10
0.1
 0.4
0.25
E  1.35  0.25  0.4
 1.45V
c) i) - Area of overlap
- Distance between plates
- Nature of dielectric medium between plates.
ii) CEff
= C1 + C2
=2+3
= 5mF
V
Q
C
1  10 4 C

5  106 F
 0.2  102 V

 20V
d) V = f
330 = 30 × l
max = 330
30
 11m
13.a) (i) Fuse - A safety device which cuts off excess current by melting to safeguard the bulbs.
(ii) Live wire is at high potential where the charges are concentrated.
(iii)
P
60W
I 
V

240V
 0.25 A
4
 16  1
0.25
Max no. of bulbs  15
No. of bulbs 
b) i) It is a transformer that is used to increase the value of the output voltage.
ii) AC source changes the polarity of the terminals hence it brings about a change in magnetic flux in the primary coils thus
inducing emf in the secondary coils.
iii) It is used to link the two coils hence concentrating field lines and preventing flux loss.
iv) - Hysteresis
- Eddy currents
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- Flux leakages
- Resistance of copper wires
v) At high voltages, the current in the transmitting cables is less, hence power loss (I²R) is greatly reduced.
14.a) Thermonic effect in this emission of electrons from surfaces of metals when they are heated. Photoelectric effect is the
emission of electrons from the surfaces of metals when irradiated with electromagnetic radiations.
b) (i) X - intercept ~ 0.5 × 1014Hz
(ii) h  ev
f
30
0.75  1014
 34
 6.4  10 Js
iii) WO = hfo
= 6.4 × 10.5 × 1014 × 10-19
= 3.2 × 10-4 J
15. a)i) It provides coherent sources
ii) - Alternating dark and bright fringes
- Dark fringes due to destruction interference
- Bright fringes due to constructive interference.
iii) - Increased distance between the fringes
- Coloured fringes are formed.
(iv) Coloured fringes are formed.
b) i) Sound becomes fainter on cooling the steam condenses creating a vacuum hence cant be transmitted.
16.a) A real image is one that can be cast on the screen while the virtual image is one that cannot be cast on a screen ü1
b) (i) Convex lens
(ii) If object distance in u the image distance is 40 - u
 1.6  10 19 
m
v
u
40  u
u
3u  40  u
3
4u  40
40
u
 10cm
4
iii)
1
1
1


f
u
v
1
1
1


f
10
30
3 1

30
2

30
f  15cm
Bur r = 2f = 2 × 15
= 30cm
iv) Simple microscope /Magnifying glass
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KERICHO SUB-COUNTY JOINT EVALUATION 2016
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3
MARKING SCHEME
1.c) i) LO = 61.4cm
(1 mark)
c) vi)
Length L (cm)
10
20
30
40
50
Extension e, cm
6.3
5.6
4.9
4.2
3.5
9.32
9.12
7.88
7.25
6.50
0.4666
0.456
0.394
0.3625
0.325
0.2172
0.2079
0.1552
0.1314
0.1056
Time for 20
oscillations
Periodic time T
(S)
Ts(S²)
d)
- axes labelled with units - 1 mark
- Scale simple and uniform - 1 mark
- 4 points plotted correctly - 2 marks
- Line passing three correctly plotted points - 1 mark
6.3  1.5
e) Slope (s)
0.22  0.024
 24.48979 cm / s 2
P
f)
 slope
4 2
P
 0.2448979
4 2
p  0.2448979  4 2
p  9.668m / s 2
2. a) iii) A = 60°
iv) D = 39°
v) 1 = 40.5°
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232/1,232/2,232/3 physics
2 = 30°
Cos 40.5
Sin 30
n  1.5208
vi)
n
b)
20
40
60
70
80
I (A)
0.025
0.050
0.700
0.075
0.095
V (v)
0.10
0.35
0.60
0.90
1.20
Log I
-1.602
-1.301
-1.555
-1.129
-1.022
Log V
-1.000
-0.450
-0.255
-0.460
0.079
Length L (cm)
d) ii)
Slope S 
 1.6  1.06
0  1.0
 0.54
iii)
K  anti log( 1.06)
k  0.0871A
  slope
n  0.54
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232/1,232/2,232/3 physics
1.
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education (K.C.S.E)
232/1
PHYSICS
PAPER 1
(THEORY)
TIME: 2 HRS
JULY/AUGUST 2016
SECTION A (25 MARKS)
Answer all the questions in this section in the spaces provided.
Figure 1 shows a measuring cylinder containing some water.
10 ml
8
Water
6
4
2
0
2.
3.
4.
5.
Determine the reading on the measuring cylinder, after four drops of water each of volume 0.6cm 3 are added. (2 marks)
A students pulls a block of wood along a horizontal surface by applying a constant force. State the reasons why the block
moves at a constant velocity.
(1 mark)
A solid weighs 18.5N on the surface of the moon. The force of gravity on the moon is 1.7Nkg -1. Determine the mass of the
solid.
(3 marks)
A bottle containing a smelling gas is opened at the front bench of a classroom. State the reason why the gas is detected
throughout the room.
(1 mark)
Figure 2 shows a flat bottomed flask containing some water. It is heated directly with a very hot flame.
Stand
Water
Hot flame
Explain why the flask is likely to crack.
(2 marks)
6. State one environmental hazard that may occur when oil spills over a large surface area of the sea.
(1 mark)
7. A balloon is filled with a gas which is lighter than air. It is observed to rise in air upto a certain height. State a reason why the
balloon stops rising.
(1 mark)
8. In verifying the pressure law of gases, the temperature and pressure of a gas are varied at constant volume. State the condition
necessary for the law to hold.
(1 mark)
9. State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium.
(1 mark)
10. Table 1 shows the results of an experiment carried out to study the properties of a spring.
Force (N)
0
6
12
18
24
Extension (cm)
0
2
4
6
8
State with a reason whether the experiment was done within the elastic limit of the spring.
11. Figure 3 shows a uniform metal rod balanced at its centre by different forces.
Determine the value of T.
(2 marks)
(3 marks)
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12. A student wearing sharp pointed heeled shoes is likely to damage a soft wooden floor. Explain
(2 marks)
13. State two ways in which the centripetal force on a body of mass m can be increased.
(2 marks)
14. a) An aero plane is moving horizontally through still air at a uniform speed. It is observed that when the speed of the plane is
increased, its height above the ground increases. State the reason for this observation.
(1 mark)
b) Figure 4 shows parts A, B and C of a glass tube.
A
B
C
Figure 4
State with a reason the part of the tube in which the pressure will be lowest when air is blown through the tube from A
towards C.
(2 marks)
SECTION B (55 MARKS)
Answer all the questions in this section in the space provided.
15. a) A cyclist initially at rest moved down a hill without pedalling. He applied brakes and eventually stopped. State the energy
changes as the cyclist moved down the hill.
(1 mark)
b) Figure 5 shows a mass of 30kg being pulled from point P to Q with a force of 200N parallel to an inclined plane. The
distance between P and Q is 22.5m. In being moved from P to Q the mass is raised through a vertical height of 7.5m.
Q
kg
30
0N
20
22.5m
7.5m
P
i) Determine the work done:
I) by the force
(2 marks)
II) on the mass
(2 marks)
III)
i) Find the wasted work.
(2 marks)
ii) Determine the efficiency of the inclined plane.
(2 marks)
c) Suggest one method of improving the efficiency of an inclined plane.
(1 mark)
16. In an experiment to determine the dentistry of sand using a density bottle, the following measurements were recorded:
Mass of empty density bottle = 43.2g
Mass of density bottle full of water = 66.4g
Mass of density bottle with some sand = 67.5g
Mass of density bottle with the sand filled up with water = 82.3g
Use the above data to determine the;
a) Mass of the water that completely filled the bottle.
(2 marks)
b) Volume of water that completely filled with the bottle.
(1 mark)
c) Volume of the density bottle;
(1 mark)
d) Mass of sand
(1 mark)
e) Mass of water that filled the space above the sand.
(1 mark)
f) Volume of the sand
(3 marks)
g) Density of the sand
(2 marks)
17. a) Explain why it is advisable to use the pressure cooker for cooking at high attitudes.
(2 marks)
b) Water of mass 3.0kg initially at 20° is heated in an electrical kettle rated 3.0KW. The water is heated until it boils at
100°C. (Take specific capacity of water 4200JKg1K-1. Heat capacity of the kettle = 450JK-1, Specific latent heat of
vaporization of water = 2.3MJkg-1)
Determine;
i) The heat absorbed by the water.
(2 marks)
ii) Heat absorbed by the electric kettle.
(2 marks)
iii) The time taken for the water to boil
(3 marks)
iv) How much longer it will take to boil away all the water.
(3 marks)
18. Figure 6 shows a stone of mass 4.0kg immersed in water and suspended from a spring balance with a string. The beaker was
placed on a compression balance whose reading was 85N. The density of the stone was 3000kgm -3 while the density of the
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232/1,232/2,232/3 physics
liquid was 800kgm-3.
Spring
balance
Stone
Figure 6
Compression
Determine the;
balance
a) Volume of the liquid displaced
b) Upthrust on the stone.
c) Reading of the spring balance.
d) Reading of the compression balance when the stone was removed from the water. (2 marks)
19. a) Figure 7 shows a velocity-time graph for the motion of a certain body.
(2 marks)
(4 marks)
(2 marks)
V(m/s)
A
B
C
O
t(s)
Figure 7
Describe the motion of the body in the region;
i) OA
ii) AB
iii) BC
b) A car moving initially at 10ms-1 decelerates at 2.5ms-2
i) Determine
I) its velocity after 1.5s
II) the distance travelled in 1.5s
ii) Sketch the velocity - time graph for the motion of the car up to the time the car stopped.
iii) From the graph, determine the distance the car travelled before stopping.
(1 mark)
(1 mark)
(1 mark)
(2 marks)
(2 marks)
(1 mark)
(2 marks)
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232/1,232/2,232/3 physics
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education (K.C.S.E)
1.
232/2
PHYSICS
PAPER 2
(THEORY)
TIME: 2 HRS
JULY/AUGUST 2016
SECTION A (25 MARKS)
Figure 1 shows a cell of e.m.f 2V connected in series with resistor R and a switch S. Voltmeters V1 and V 2 are connected
across the cell and the resistor respectively.
V1
R
S
2V
V2
Figure 1
a) State the reading of V1 with S open.
(1 mark)
b) With S closed, V1 reads 1.6V, state the reading of V2.
(1 mark)
2. One method of producing a weak magnet is to hold a steel rod in the North -South direction and then hammer it continuously
for some time. Using domain theory of magnetism explain how this method works.
(2 marks)
3. When the cup of an uncharged electroscope is irradiated with light of high frequency the leaf of the electroscope rises.
Explain this observation.
(3 marks)
4. A diverging lens of focal length 10cm produces a virtual image half the size of the object. Find the distance between the
object from the lens.
(3 marks)
5. Figure 2 below shows two polythene spheres P and Q suspended using nylon thread.
6.
Figure 2
P
Q
Draw a diagram to show how the two spheres would behave if only P is rubbed with a cloth.
Figure 3 shows an electromagnetic spectrum.
A
B
C
Visible light
D
E
F
Figure 3
Given that F has the shortest wavelength;
b) State one application of E.
7. Explain why alternating current (a.c) is used for transmitting electricity over long distances.
8. The following reaction is part of a radioactive series.
210
83
(1 mark)
(1 mark)
(1 mark)
(1 mark)
X
21084Y alpha
bc Z
Identify the radiation r and determine the values of b and c.
(3 marks)
9. State two factors that increase the photoelectric emission of a metal.
(2 marks)
10. A pin is placed at the bottom of the beaker of depth 14.5cm. The beaker is then filled with Kerosene. By using another pin on
the side of the beaker and observing from the top, the distance of image of the pin in the beaker is found to be 4.5cm from the
bottom.
Determine the refractive index of kerosene.
(3 marks)
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232/1,232/2,232/3 physics
11. Figure 4 below shows an alternating current (a.c) connected across a diode D and resistor R.
D
R
Figure 4
a) Show on the diagram where a C.R.O can be connected to display the output voltage.
b) On the axes provided, sketch the output as observed in the C.R.O in 9a) above.
(1 mark)
(1 mark)
V(v)
t(s)
12. Figure 5 below shows the section of a conductor held between two bar magnets.
Figure 5
Indicate with an arrow on the diagram the direction in which the conductor should be moved in order to cause current to flow
as shown.
(1 mark)
SECTION B 55 MARKS
13. a) The figure 6 shows two coils A and B placed close to each other. A is connected to a steady D.C supply and a switch B is
connected to a sensitive galvanometer.
Coil A
Coil B
sensitive
galvanometre
Figure 6
i) The switch is now closed. State the observation made on the galvanometer.
(2 marks)
ii) Explain what would be observed if the switch is then opened.
(2 marks)
b) The primary coil of a transformer has 1000 turns and the secondary coil has 200 turns. The primary coil is connected to a
240V ac mains supply.
i) Explain how e.m.f is induced in the secondary coil.
(2 marks)
ii) Determine the secondary voltage.
(3 marks)
iii) Determine the efficiency at the transformer gives that the current in the primary coil is 2.0A and in secondary coil is
0.80A.
(2 marks)
14. a) i) Figure 7 shows a ray of light incident on a plane mirror at O.
50°
O
Figure 7
The mirror is rotated clockwise through angle 30° about an axis perpendicular to the paper and through O, determine the
angle through which the reflected ray rotates.
(2 marks)
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232/1,232/2,232/3 physics
ii) Find the number of images formed when an object is between two mirrors placed 45°.
(2 marks)
iii) In a certain pinhole camera, the screen, is 10cm from the pinhole. When the camera is placed 6m away from a tree a sharp
image of the tree 16cm high is formed on the screen. Determine the height of the tree.
(2 marks)
b) In an experiment to determine the focal length of a concave mirror, a group of students collected some data and used the
results to plot the graph shown in figure 8. Using the graph above, determine;
5
x
Magnification (m)
4
x
3
x
2
x
1
x
10
0
-1
20
30
40
50
Image distance V(cm)
i) the object position when the image position is 45cm.
ii) the slope of the graph.
iii) find the focal length of the mirror given that m= v/f-1
15. Figure 9 is a diagram of cathode ray tube. M and N are parallel vertical plates.
(3 marks)
(2 marks)
(1 mark)
S
N
~
Spot
Screen seen
from front
M
F
M
N
+ High voltage
Figure 9(a)
Figure 9(b)
a) When switch S is open, spot is seen at the centre of the screen as shown in figure 9.
i) State what happens to the spot when S is closed.
(1 mark)
ii) State what would happen to the spot if the potential difference across MN is increased.
(1 mark)
iii) State what would be seen on the screen if the battery is replaced with an alternating e.m.f of;
I) a low frequency of about 1HZ
(1 mark)
II) a high frequency of about 50HZ.
(1 mark)
b) Explain the process by which electron are produced at F.
(2 marks)
c) State with a reason how the brightness of the spot can be increased.
(2 marks)
d) The accelerating voltage of the tube is 1000V and the electron current in the beam is 1.5mA. Determine the energy to the
screen per second.
(3 marks)
16. Figure 10, shows a circuit that may be used to charge a capacitor.
S
mA
C
5v
R
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232/1,232/2,232/3 physics
Figure 10
i) State the observation on the milliameter when the circuit is switched on.
ii) Explain the observation (i) above.
b) The circuit in figure 10 is left on for some time. State the value of p.d across;
i) The resistor R.
ii) The capacitor C
c) Sketch the graph of potential difference (V) across R against time.
d) Figure 11 shows three capacitors connected to a 10V battery.
-
10V
(1 mark)
(2 marks)
(1 mark)
(1 mark)
(1 mark)
+
3.0 F
4.0 F 5.0 F
Figure 11
Calculate
i) the combined capacitance of the three capacitors.
ii) the charge of
17. a) State one difference between light and sound wave.
b) Briefly describe how sound is propagated in air.
c) Figure 12 shows a set up made by form two students to study an aspect of a wave.
(3 marks)
(3 marks)
(1 mark)
(1 mark)
Electric bell
Steam from
boiling water
Water
Figure 12
i) State what happens to sound from the bell as the bottle and contents are cooled to 0°C.
(1 mark)
ii) Explain the observation in (ii) above.
(2 marks)
d) A girl standing on a level ground between two high walls claps her hands. she hears an echo from one wall after 0.7
seconds and from the other wall 0.2 seconds later. Determine the distance between two walls. (Speed of sound in air =
330m/s)
(3 marks)
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232/1,232/2,232/3 physics
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education (K.C.S.E)
232/3
PHYSICS
PAPER 3 (PRACTICAL)
TIME: 2½ HRS
JULY/AUGUST 2016
QUESTION 1
You are provided with the following;
- An ammeter
- A voltmeter
- Two cells (size D)
- A cell holder
- A switch
- A wire labelled L mounted on a millimeter scale
- A micrometer screw gauge (to be shared)
- Six connecting wires at least four with crocodile clips
Proceed as follows;
a) Using a micrometer screw gauge, measure and record the diameter d of the wire L.
(1 mark)
d = ....................mm
d = ...................m
b) Place the two cells in series in the cell holder and use the voltmeter to measure the total electromotive force (emf) E 0 of the
battery.
(1 mark)
E0= .............................................v.
c) Starting with the switch open, connect the circuit as shown in figure 1. P and Q are points on the wire L such that PQ is
60cm. (PQ should remain 60cm throughout the experiment) N is a point on the wire such that PN is 10cm (0.1m)
Figure 1
d) i) Close the switch and record the current.
(1 mark)
I = ...............................A
ii) Measure and record in table 1 in the potential differences across PN.
iii) Measure and record the potential difference across PN for the other values of PN shown in table 1 and complete the table.
(The current is expected to remain constant)
Hint: The switch should be closed only when reading the voltmeter.
Table 1
e)
f)
On the grid provided, plot a graph of resistance (y -axis) against length.
From the graph, determine;
i) the slope S and its units.
ii) the constant k and its units given that; S = 4k
pd2
g) Determine constant t given that; t = E0 - Vn
I
where Vn is the p.d at PN = 0.6m.
(6 marks)
(3 marks)
(3 marks)
(3 marks)
(2 marks)
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232/1,232/2,232/3 physics
QUESTION 2
You are provided with the following;
- A meter rule
- A spring balance
- A weight of 2N with a hook (2, 100g masses)
- A stand
- Knife edge support
- Two light strings about 10cm long
Proceed as follows;
a) Using the string provided make two loops to be used as hooks L1 and L2 in the diagram 2.
b) Suspend the spring balance from a clamp and using one loop to support the rule from the spring so that the loop L2 is on
85cm mark.
c) Support the other end of the rule with a knife edge at the 10cm mark so that the rule is horizontal.
d) Using loop 1 suspend the 2N weight at a distance d = 10cm from the knife edge as shown and take the readings of the spring
balance, F. Record the results in the table.
e) Adjust the distance d to 20, 30cm etc and each time recording the readings of the balance to complete the table.
Spring balance
85cm
10cm
Metre rule
d
L1
L2
Knife
edge
Stand
2N
Diagram 2
Results
a)
Distance (d)
10
20
30
40
50
60
70
Force (N)
i) Plot graph of force F against distance d(cm).
(5 marks)
i) the slope
(3 marks)
ii) the value of F when d = 0
(2 marks)
iii) Using the information from your graph, determine the constant k and m in the equation below and state units. F
represents the reading of the balance and d is as shown in the above.
(4 marks)
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232/1,232/2,232/3 physics
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Kenya Certificate of Secondary Education (K.C.S.E)
MARKING SCHEME
Physics (232/1)
Paper 1
July/August 2016
SECTION A
Reading = 7.6 + (0.6 x 4)1
= 7.6 + 2.4
= 10.0ml1
Friction force is equal to the applied force/resultant force is zero; 1
m = w/g; 1
= 18.5/1.71
= 10.88kg1
The gas diffuses;/moves from region of high concentration to low concentrationü1
Glass is a poor conductor;1
Unequal/uneven/non uniform expansion leads to cracking;1
Reduces inflow of air/oxygen; /Causes aquatic animals to die or suffocate/beaches become dirty/reduces sunlight entry; ü1
Stops rising when upthrust is equal to the weight of the balloon; (and its contents) 1
Mass is constant/fixed;/given mass/particular massü1
The height of its c.o.g above the ground is constant; Position of c.o.g above surface is constant.ü1
Yes; ü1
The values of f/e = constant1
Clockwise moments = anticlockwise moments;1
4 x 35 + T x 50 = 40 x 8
T = 40 x 8 - 4 x 35
50
= 3.6N1
The sharp heeled shoe exerts great/high/much pressure; 1
Due to small (surface) area;1
Increasing angular velocity;1
a) Air above the plane moves faster than air below creating a low pressure above the plane hence lifting; due to the pressure
difference.1
b) At B; (narrowest part)ü1 because the C.S.A is smaller hence air moves faster in that region 1
a) Potential energy ..... kinetic energy ..... Heat + sound; or p.e ....k.e ...heat + soundü1
b) i) I) w.d = fd = 200 x 22.5 1
= 4500J; 1
II) mgh=30 x 10 x 7.5J; 1
mgh = 30 x 10 x 7.5
=2250J; 1
III) fd - mgh = 4500 - 2250;1
= 2250J;1
ii) Work out x 100%1
Work in
= 2250 x 100% = 50%1
4500
c) (Reduce friction) by oiling/greasing, smoothening surface/using rollers;1
a) (66.4 - 43.2)g;1
= 23.2gü1
b) 23.2g = 23.2cm31
1g/cm3
c) 23.2cm3;1
d) (67.5 - 43.2g) = 24.3g1
e) 82.3 - 67.5 = 14.8g 1
f) Volume of bottle - volume of added waterü1
= 23.2 - 14.8; 1
1
= 8.4cm3;1
g) m/v = r 24.3/8.4 1
= 2.893g/cm31
Page | 279
232/1,232/2,232/3 physics
17. a) At high altitudes pressure is low so b.p is low;1 so pressure cooker increases pressure inside which raises b.p; or pressure
inside the cooker is higher raising the b.p1
b) i) McDq = 3 x 4200 x 80; 1
= 1,00800J; 1
ii) CDq = 450 x 80;1
= 36,000J1
iii) pt = McDq + CDq 1
3000t = 1008000 + 36000
= 104,400;1
t = 104,400 = 348s;1
3000
= 5.8min
iv) Mlv = pt; ü1
3 x 2.3 x 106 = 3000t;1
t = 2300sec; 1
18. a) m/v = dü1
4/v
= 3000;
v = 1.33 x 10-3m3;1
b) d = m/v; or m = 800 x 1.33 x 10 -31
m = 1.064kg; 1
Weight of displaced liquid = mg = 10 x 1.064;1
= 10.64N;1
c) 40 - 10.641; = 29.36N;1
d) 85 - 10.641 = 74.36N;1
19. a) i) OA - Body moves from rest at constant acc. or uniform acc;ü1
ii) AB = decreasing /reducing acc;1
iii) BC constant velocity/zero zcc;1
b) i) v = u + at;ü1
v = 10 - 2, 5 x 1.5
= 6.25m/s1
II) s = ut + ½at2; 1
=10(1.5) - ½ x 2.5 x 1.521
= 12.1875
~ 12.19m1
III) v = u + at; 1
t = 10/25 = 4s 1
ii)
V(m/s)
10
O
4
t(s)
iii) Distance = area of triangle;ü1
= ½ x 4 x 10 = 20m;ü1
Page | 280
232/1,232/2,232/3 physics
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
1.
2.
3.
4.
Kenya Certificate of Secondary Education (K.C.S.E)
MARKING SCHEME
PHYSICS (232/2)
JULY/AUGUST 2016
a) V1 = 2.0V 1
b) V2 = 2.0 - 1.6 = 0.4V
1
Hammering causes domains to vibrate 1
As they settle some face or align north-south due to earth’s magnetic
field
1
Electrons absorb energy and are ejected from the cap leaving
1
electroscope positively charged
1
The leaf is then repelled by the plate
1
V
/u = ½ U = 2V
1 for eqn
1
/f = 1/u + 1/v
-1/10 = ½V - 1/v -1/10 = -½V 1
substitution
V=5
U = 2V = 2 x 5 = 10cm 1
5.
1
correct charge
distribution attraction
a) Microwaves
1
b) -Sterilisation of surgical equipment 1
any one
- Treating cancer ie killing malignant tissues
- Detect flaws in metals and forgeries in art.
7. -Alternating current can be stepped up and down OR
1
any one
-Alternating voltage can be stepped up or down.
- Reduces power losses
8. r = ß beta
1
b = 86
1
c= 206
1
1
Using a radiation of higher frequency 1
1 mark each
10. n = real depth =
14.5
1
formula
apparent depth 10
1
substitution
= 1.45
1
6.
11. a)
R to C.R.O
1
b)
V(v)
1
at least two outputs
t(s)
Page | 281
232/1,232/2,232/3 physics
12.
1 should have an arrow
13. a) i) Pointer deflects up to a certain maximum value and then returns
1
to zeroü 1
OR
Momentary deflectionü2 2
ii) There is deflection in the opposite direction ü1 flux in A falls, flux 1 in B also falls inducing e.m.f in opposite directionü
1
b) i) Current in the primary coil is constantly charging its direction so 1 the resulting flux is constantly changing its
direction. Therefore alternating emf is induced in secondary coil. 1
ii) Vs/Vp = Ns/Np
1
formula
Vs = 200
1
substitution
240 100
Vs = 48N
1
iii) IsVs x 100% 0.8 x 48 x 100%
1 for
IpVp
0.2 x 240 1
substitution
= 80%
1
ans
14. a) i) The reflected ray moves by twice the angle of rotation
1
2 x 30 = 60° 1
ii) n = 360° - 1
q°
360 - 1
1
substitution
45
= 7 images
1
iii) m = V/U = hi/ho
= 10
= 16 1
substitution
600
ho
ho = 16 x 600 = 960 = 9.6cm
1
10
b) i) When V = 45, M = 3.5
1
but M = v/u U = 45/3.5
1
U = 12.85cm
1
ii) Slope = 3.5 - 0 = 3.5
1
45 - 10 35
= 0.1cm-1
1
iii) f =
1
= 1 = 10cm 1
slope
0.1
15. a) i)
Deflects towards the positive plate or
1
any one
Deflects towards plate N or
Deflects away from M
ii)
Deflection will be greater 1
iii) I)
Spot moves back and forth or
1
any one
Spot moves to and fro
There is horizontal oscillation
II) There will be a horizontal line 1
b) Electrons are given offü as a result of heat produced by the 1current i.e through thermionic emission
1
c) Increasing the filament current üso that more electronsü are released 2
d) P = VI
1
= 1000 x 1.5 x 10-3
1
= 1.5J/S or 1.5W
1
16. a) i) High current which fall off to zero 1
ii) Currently flows when the capacitor is changing when fully 1
charged current flow stops ie (no current) and p.d is equal to 1 charging voltage.
b) i) VR = OV
ii) VC = 5V
1
Page | 282
232/1,232/2,232/3 physics
c)
d) i) 1 = 1 + 1 = 9
Ct 4 5
20
Ct = 20 mF
1
9
Ct = 20 + 3.0 = 5.22mF 1
9
ii) QV = 20 x 10mC
9
= 200mC = 22.2mC
1
9
1
Same charge on 5.0mF capacitor = 22.2mC
17. a)
Light waves
Sound waves
-Transverse in nature
Longitudinal
Electromagnetic
Mechanical
formula
substitution
1
b) Sound waves exerts varying pressure on the air creating compressions and rare factions in the air which moves along the
air column.
c) i) Sound becomes less audible until it cannot be heard any more
ii) Steam condenses creating a vacuum around the bell hence sound being mechanical wave cannot be transmitted.
d) d = ½Vt
= ½ x 330 x (0.7 + 0.9)
d = 264m
Page | 283
232/1,232/2,232/3 physics
THARAKA NORTH/SOUTH SUB-COUNTIES FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education (K.C.S.E)
MARKING SCHEME
PHYSICS (232/3)
July/August 2016
a) d = 0.30mm 1
d = 0.003m
b) E0 = 3.2V + 0.1V
1
d) I = 0.40A + 0.02A
1
ii)
Length PN (m)
0.1
0.2
0.3
0.4
0.5
0.6
P.d (v)
0.3
0.76
1.0
1.3
1.7
2.0
Resistance V/I(Ω)
0.75
1.75
2.5
3.25
4.25
5.0
Each value of p.d(v) half mark + 0.1 3
Each value of resistance (Ω) half mark + 0.1
e) Label
1
Plotting
1
Line
1
f) i) Gradient = 1.25 - 0 1
0.15 - 0
= 1.25
0.15
= 8.33Ωm-1
2 ans and units
ii) s = 4k
Ωd2
K = s x d2
4
= 8.33 x 22/7 x (0.003)2 1
4
= 0.0000589
= 5.89 x 105 Ωm 2 ans and units
g) t = E0 - Vn
I
= 3.2 - 2.0 1
0.4
= 1.2/0.4 = 3
1
3
Page | 284
232/1,232/2,232/3 physics
i)
(6 marks)
Distance (d)
10
20
30
40
50
60
70
Force (N)
0.75
1.00
1.30
1.55
1.85
2.10
2.35
Slope = ∆Y = 1.80 - 0.75 = 1.05
∆X
50 - 10
40 = 0.0265N/cm
ii) Read from graph and extrapolation
Extrapolation
1mk
2mks
b) F = 2md + 40k
Comparing the equation to that of
y =- MX + C
Slope = 2m
substitution 1mk
2mks
0.0265 = 2m
m = 0.0265 = 0.01325N/cm
2
Y = intercept of graph = 40k
substitution 1mk
K = 0.45n = 0.01125N
40
Page | 285
232/1,232/2,232/3 physics
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
Kenya Certificate of Secondary Education
232/1
PHYSICS
Paper 1 (Theory)
July/August 2016
Time: 2 Hours
SECTION A : (25 MARKS)
1. Figure 1 is a sketch of part of a micrometer screw gauge.
40
35
Insert the main scale for the micrometer screw gauge to read 5.86mm.
(1 mark)
2. In figure 2, a porous pot with a straw connected to it was filled with hydrogen gas to a pressure equal to atmospheric pressure.
The pot was inverted such that the straw was immersed in water as shown.
Porous Pot
Straw
Water
The water was found to soon rise up the straw to a great height. Explain this observation.
3. Figure 3 below shows two thermometers placed at equal distance from a tank containing hot water.
X
(3 marks)
Y
Painted
black
Painted
white
4. Explain why water does not wet a waxed glass surface.
5. The springs shown in the arrangement in figure 4 below are identical.
(1 mark)
(1 mark)
(1 mark)
90N
Page | 286
232/1,232/2,232/3 physics
Given that the 90N weight causes a total extension of 25cm, determine the spring constant of each spring.
(3 marks)
6. State and define the two fixed points of the Celcius scale.
(2 marks)
7. Figure 5 below shows a uniform metre rule of weight 3N supporting two weights. The metre rule is pivoted somewhere such
that it is horizontally balanced. (pivot not shown)
15cm
70cm
6N
4N
100cm
Displacement (m)
Velocity m/s
The 6N weight is at 15cm mark while the 4N weight is at 70cm mark. Determine the position of the pivot from zero cm mark.
(3 marks)
8. A force of 200N is applied on a 10kg block on a horizontal surface. The body attains an acceleration of 16m/s 2. Determine the
coefficient of friction between the block and the surface.
(3 marks)
9. A body is projected vertically upwards and returns back to its point of projection. In terms of its velocity, describe its motion.
(3 marks)
10. State the reason why trucks carrying heavy loads are fitted with many tyres.
(1 mark)
11. A mass of 200g is tied to a string and whirled in a vertical scale of radius 48cm at a speed of 12m/s. Calculate the tension in
the string at the top of the circular path.
(3 marks)
12. State how the pressure in a moving fluid changes when the velocity of the fluid increases.
(1 mark)
SECTION B : (55 MARKS)
13. A student measured the mass of an empty container and found it to be 70g. He then put 80 drops of oil in the container and the
mass of the container and its contents became 70.12g. Given that the density of the oil used is 0.75g/cm3.
a)Determine :
i)Volume of the oil put in the container.
(2 marks)
ii)Average volume of one drop
(2 marks)
b) One such drop is put on the surface of water where it spread into a thin circular film of diameter 100cm.
i)Estimate the diameter of the oil molecule.
(3 marks)
ii) State the assumption made in b(i) above.
(1 mark)
14. a)What is the meaning of term uniform acceleration ?
(1 mark)
b) The motion of a body is described by the graph shown in the figure 6(a).
Time (s)
Time (s)
Sketch a velocity-time graph for the motion on the set of axes in figure 6(b)
(1 mark)
c) A body of mass 0.5kg falls from an 80m tall building and penetrates to the ground to a depth of 20cm. Determine :
i)The velocity at which the body strikes the ground.
(3 marks)
ii) The average retardation as the body penetrates the ground.
(3 marks)
iii) The retarding force on the body.
(2 marks)
15. a) State the law of conservation of energy.
(1 mark)
b) Figure 7 is an illustration of a simple pendulum.
88.3cm
95.5cm
R
P
Q
Page | 287
232/1,232/2,232/3 physics
i) Describe the energy transformation which takes place when the pendulum swings from P to R.
(2 marks)
ii) Given that the length of the pendulum is 95.5cm and it rises such that the vertical length from the level of support is
88.3cm, calculate the maximum velocity of the bob.
(3 marks)
c) The pulley system shown in figure 8 is used to lift a load of 40N through a height of 2m.
30N
40N
Given that the effort applied is 30N, determine :
i) Work done in lifting the load.
ii) Work done by the effort.
iii) Efficiency of the system.
16. a)Figure 9 shows a set up to investigate one of the gas laws.
(2 marks)
(2 marks)
(2 marks)
Upthrust U, (N)
i) Name the gas law being investigated.
(1 mark)
ii) Give two reasons for using the concentrated sulphuric acid index.
(2 marks)
iii) What is the purpose of the water bath ?
(1 mark)
iv) State two measurements that should be taken in this experiment.
(2 marks)
v) Explain how the measurements taken in (iv) above may be used to verify the law.
(3 marks)
b) A gas has a volume of 30cm3 at 18oC and normal atmospheric pressure. Calculate the new volume of the gas if it is heated
to 54oC at the same pressure.
(3 marks)
17. In an experiment to determine the density of a liquid, a uniform cylindrical metal rod of cross-sectional area, A = 6.25cm2 was
hung from a spring balance and lowered gradually into the liquid. The upthrust for various submerged heights was
determined. The results obtained are shown on the graph in figure 10.
0.7
*
0.6
*
0.5
*
0.4
*
0.3
*
0.2
*
0.1
*
*
0
1
2
3
4
5 -2 6
Submerged Heat, h(x10 m)
7
Page | 288
232/1,232/2,232/3 physics
i) Determine the slope of the graph.
(3 marks)
ii) Given that the equation of the graph is U = Ah g where is a constant. Use the graph to determine the value of
.
(3 marks)
18. In an experiment to determine specific latent heat of vaporization of steam, steam of mass 6g at 100 oC is passed into water of
mass 400g at 15oC. The final temperature of the mixture is 24.4 oC.The container absorbs negligible heat. (Specific heat
capacity of water is 4200Jkg-1k-1)
i) Derive an expression for the heat, Q, lost by the steam as it condenses to water at 24.4 oC.
(3 marks)
ii) Calculate the heat, H, gained by water.
(2 marks)
iii) Determine the specific latent heat of vapourisation of steam.
(2 marks)
Page | 289
232/1,232/2,232/3 physics
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
Kenya Certificate of Secondary Education
232/2
PHYSICS
Paper 2 (Theory)
July/August 2016
Time: 2 Hours
SECTION A : (25 MARKS)
1. Figure 1 below shows a vibrating hack saw blade.
K
L
The time interval for the blade to move from K to L is 0.008 seconds. Determine the frequency of vibration.
2. Figure 2 is an illustration of short sightedness.
(3 marks)
Draw a separate diagram to illustrate how this defect can be corrected.
(3 marks)
3. Define the term sulphation as applied to lead acid cells.
(1 mark)
4. A student making a simple cell in the laboratory realised that the current quickly falls to a very small value. State a possible
cause for this.
(1 mark)
5. A device is marked 1000W 240V. What fuse rating would be suitable for the device.
(3 marks)
6. A step up transformer connected to a 40V supply is designed to deliver power to a lamp rated 240V 100W. Given that
transformer is 95% efficient, determine the current in the primary winding when the lamp is connected.
(3 marks)
7. Explain with the aid of diagrams how you can charge an electroscope negatively by induction method.
(3 marks)
8. Figure 3 shows ultra violet radiation striking a clean zinc plate on a negatively charged gold leaf electroscope.
Clean Zinc plate
Explain why the leaf of the gold leaf electroscope falls.
(2 marks)
9. Figure 4 shows a set up used by a student to investigate electromagnetic induction. He extends the spiral spring until the South
pole of the magnet is in the middle of the coil and releases the spring. The e.m.f induced is measured using an oscilloscope
connected across A and B.
Spring
Pointer
N
Ruler
Magnet
S
A
Solenoid
B
Page | 290
232/1,232/2,232/3 physics
The oscilloscope has its time base switched off. Explain why as the magnet oscillates a dot appears oscillating vertically on the
screen.
(2marks)
10. Figure 5 shows a wire XY at right angles to a magnetic field. XY is part of a circuit containing a galvanometer.
X
N
G
S
Y
Indicate on the diagram the direction XY is moved for current to flow in the direction shown.
11. Explain how a cloud chamber could be used to distinguish between alpha and beta radiations.
12. State one use of ultra violet waves.
SECTION B :
(1 mark)
(2 marks)
(1 mark)
13. a) Define the term critical angle.
(1 mark)
b) A ray of light passes in a glass block as shown in the figure 6 below.
Glass
Given that the refractive index of glass is 1.5, determine angle .
c) Figure 7 shows a ray of light travelling through successive media.
(3 marks)
c
Air
b
Water
a
Glass
Air
70°
Given that the refractive index of glass is 3/2 while that of water is 4/3 determine :
i)
angle a
ii)angle b
iii)angle c
14. a)Figure 8 is an illustration of a wave pattern.
25
50
(2 marks)
(2 marks)
(2 marks)
75 Distance(cm)
i) State with reason the type of wave shown.
(2 marks)
ii) Determine the wavelength of the wave.
(1 mark)
iii) Calculate the frequency of the wave given that the speed of the wave is 9m/s.
(3 marks)
b)Figure 9 show s monochromatic source of light L behind a barrier with a single slit S placedbehind another barrier with two
identical slits S1 and S2. A screen PQ is placed in position as shown.
P
L
S1
S
S2
Q
Page | 291
232/1,232/2,232/3 physics
i) Explain what is observed on screen PQ.
(2 marks)
ii) What is the significance of S1 and S2 ?
(1 mark)
15. a)State two differences between the image formed when the object is between C and F and the oneformed when the object
between F and P by a concave mirror.
(2 marks)
b)An object is placed 60cm from of a concave lens of focal length 40cm. Determine the position of
the image.(3 marks)
c) Figure 10 chows a graph drawn from an experimental data to determine the focal length of a convex lens.
(U+V)cm
*
70
*
60
*
50
*
40
*
30
*
20
*
10
0
100
200 300
400 500
600 700
(UV) cm²
i) Determine the slope of the graph.
ii) Determine the focal length of the lens.
16. a) State Lenz’s law of electromagnetic induction.
b)
(3 marks)
(3 marks)
(1 mark)
G
S
N
A wire placed between the poles of two permanent magnets is connected as shown in figure 10.
i)
State and explain what is observed when the wire is moved up and down.
(2 marks)
ii) Suggest two ways of altering the magnitude of the effect you have stated in (i) above.
(2 marks)
c) Explain why the core of a transformer is :
i)\laminated
(1 mark)
(1 mark)
d) A heater rated 3KW is used for 30 minutes everyday for 30 days. Calculate the cost of the electricity consumed in the 30
days given that its charged at Ksh.7.00 per unit.
(3 marks)
17. Figure 11 shows the main parts of an X-ray tube.
EHT
Q
Low D.C
Voltage
Oil in
R
P
A
Oil out
Q
Y
Shield
Page | 292
232/1,232/2,232/3 physics
a) Name the parts labelled Q and R.
(2 marks)
b) Explain the effects on the X-rays produced when :
i) The ammeter reading is raised.
(2 marks)
ii) The extra high tension voltage (EHT) is increased.
(2 marks)
c) State with reason the material used to make the part labelled P.
(3 marks)
d) The Y-gain of a C.R.O is connected at 50V/cm. An alternating voltage source connected to the input terminal produces a
sine wave curve with an amplitude of 3.5cm. Determine the highest voltage produced by the source.
(3 marks)
18. Figure 12 shows a network of 4 resistors.
4
2.75
V
2
2
A
12V
(3 marks)
(2 marks)
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
-
PHYSICS
Paper 3
July/August 2016
CONFIDENTIAL INSTRUCTIONS
Each candidate will require :
Question 1
Each candidate will require :
a boiling tube
a measuring cylinder (10ml or 25ml)
a half metre rule
some water in a container
a stand complete with boss and clamp
vernier callipers (may be shared)
a glass block (approximately 10cm x 6cm x 2cm)
a plain sheet of paper
five optical pins
Question 2
an ammeter (0 - 2.5A)
a voltmeter (0 - 5V)
nichrome wire (SWG 28) mounted on a mm scale
a switch
two new dry cells (size D)
a cell holder
six connecting wires at least four with crocodile clips at one end
a micrometer screw gauge (may be shared)
Page | 293
232/1,232/2,232/3 physics
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
1.






232/3
PHYSICS
Paper 3
(Practical)
July/August 2016
Time: 2½ Hours
PART A
You are provided with the following :
a boiling tube
a measuring cylinder
a half metre rule
water in a container
a stand complete with boss and clamp
vernier callipers (may be shared)
Proceed as follows :
a) Using the vernier callipers measure the internal diameter, d, of the boiling tube.
d = ........................................................ cm.
b) i) Clamp the boiling tube vertically as shown in the figure 1 below.
(1 mark)
h
-
ii) Using the measuring cylinder pour 15cm3 of water into the boiling tube. Measure and record in table 1 the height h, of water
in the boiling tube.
iii) Repeat the procedure in b(ii) for other volumes of water, V, shown in the table.
Volume, V, of water (cm³) Height, h, of water (cm³)
15
20
25
30
35
40
(5 marks)
c) Plot a graph of V(y-axis) against h on the grid provided.
(5 marks)
d) i) From the graph determine the slope S and its units.
(3 marks)
ii) Determine the value of constant k given that 4S = kd 2.
(2 marks)
PART B
You are provided with the following :
A glass block
A plain sheet of paper
five optical pins
a half metre rule
Proceed as follows :
a) Measure the length, l, of the glass block.
l = ...................................................... cm
b) Place the glass block on the plain sheet of paper and trace its outline.
(1 mark)
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232/1,232/2,232/3 physics
c) Place a pin P1 firmly at the middle of one end of the glass block as shown in figure 2 below.
P3
P2
I
P1
P4
P5
X
d) With your eye at the opposite end of the block, place pins P 2 and P3 so that they are in line with the image I of pin P1 as
shown in figure 2. Similarly locate the image I using pins P 4 and P5.
e) Remove the glass block and produce P3P2 and P5P4 to their point of interection.
f) i) Measure the distance, X, shown in figure 2.
X = ..................................................cm
(1 mark)
ii) Determine the constant k given that
k= l
x
(2 marks)
iii) What does constant k represent ?
(1 mark)
2. You are provided with the following :
- an ammeter
- a voltmeter
- a wire mounted on a mm scale
- a switch
- two cells (size D)
- a cell holder
- a micrometer screw gauge (may be shared)
- six connecting wires at least four with crocodile clips.
Proceed as follows
a) Using the micrometer screw gauge, measure and record the diameter d of the mounted wire
(1 mark)
d = ..............................................mm
d = .............................................. m
b) Place the two cells in series in the cell holder and use the voltmeter to measure the electromotive
E = ........................................................... V
(1 mark)
Set up the apparatus as shown in the circuit in figure 3 below.
c) Starting with the switch open, connect a crocodile clip on the mounted wire such that l = 30cm (0.3m)
d) i) Close the switch and record in table 2 the voltmeter and ammeter readings.
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232/1,232/2,232/3 physics
ii) Repeat the procedure in d(i) for other values of l shown in the table. Complete the table.
Table 2
l (m)
0.3
0.4
0.5
V (volts)
I (A)
0.6
0.7
0.9
e) On the grid provided, plot a graph of resistance (y-axis) against length.
(5 marks)
f) From the graph, determine:
i) The slope S and its units.
(3 marks)
ii) The constant q and its units given that q = pd2S
4
(2 marks)
iii) Determine the constant r and its units given that : r = E - V
I where V and I are values of current and p.d. at l = 0.9m.
(3 marks)
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NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
PHYSICS
Paper 1
July/August 2016
MARKING SCHEME
SECTION A :
40
1.
35
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Hydrogen gas diffuses out of the pot at a faster rate than air gets in. 1
Pressure in the pot reduces below the atmospheric pressureü1. Hence the greater atmospheric pressure on the surface of the
water pushes the water up the tube. 1
a) Thermometer x shows a higher reading 1
b) The black painted surface radiates heat at a faster rate than the white surface 1
The cohesion force between the water molecules is greater than adhesion force between water molecules and the waxed glass
surface 1
F = Ke 1
or
F = Ke
e = e 1 + e2
e = e 1 + e2
90 + 90 = 0.25 1
0.25 = 30 + 45
3k 2k
k
k 1
K = 300N/m 1
k = 300N/m 1
The fixed points are ice point / lower fixed point and steam point / upper fixed point 1
The lower fixed points in the Celsius scale is the temperature of pure melting ice at standard atmospheric pressure while the
upper fixed point is the temperature of steam from pure boiling water at standard atmospheric pressure 1
Clockwise moment = anticlockwise moment 1
or F1S1 = F2S2 or F1d1 = F2d2
6 (0.35 - x) = 3x + (0.2 + x)4 1
x = 0.1m
The position the pivot is at 40cm marks
Resultant force (force causing the motion)
F = ma
= 10 x 16
= 160N 1
Friction = 200 - 160
= 40N
F = mR = mmg ü1 either formula or m =
40
substitution
100
= 0.4 1
The velocity of the body reduces uniformly upto the maximum height when it is momentarily at rest 1
Then the velocity increases uniformly in the opposite direction 1
To increase the area of the contact with the ground inorder to reduce the pressure 1
T = mv2 - mg 
r
= 0.2 x 122 - 0.2 x 10 
0.48
= 58N
Pressure reduces 1
SECTION B
a) i)
m = 70.12 - 70 = 0.12
1
ii)
Volume of one drop =
b) i)
V = h x A 1
h=
1=
0.002
22
/7 x 50 x 50 1
= 2.545 x 10-7cm 1
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Velocity m/s
ii) Mono molecular layer of oil forms the patch 1
14. a) The velocity of a body changes equally at equal time intervals 1
b)
Time (s)
c)
i)
v2 = u2 + 2as 1
v2 = 02 + 2 x 10 x 80 1
= 1600
v = 40m/s 1
ii) v2 = u2 + 2as 1
0 = 402 + 2 x 0.2 x a 1
a=
iii)
15. a)
b)
ii)
c)
ii)
iii)
= -4000m/s2 1
Retarding force F = ma

= 0.5 x 4000 either formula or substitution
= 2000N 1
i) Energy can neither be created nor destroyed but can be transformed from one form to another 1
i) At P the bob has P.E which is converted to KE between P and Q, 1 then from K.E to P.E between Q and R 1
½mv2 = mgh 1
v = Ö0.072 x 2 x 10 1
= 1.2m/s 1
i)
Work = force x distance
= 2 x 40
= 80J
work done by effort
w = 4 x 30
= 120J
Efficiency =
= 80 x 120%
120
= 66.67%
16. a)
i) Charle’s law ü1
ii)
I. To trap air 1
II. Dry the air 1
iii)
To warm / heat the trapped air 1
iv) I. volume / length of air column ü1
II. Temperature of the water bath or trapped air 1
b) Draw the graph of volume / length of trapped air against absolute temperature 1
The graph is a straight line 1 showing that volume is directly proportional to absolute temperature 1
b) V1 = V2
T1 T2 1
1
= 26.697cm3
= 26.7cm3 ü
17. i) Slope = charge in Y
charge in X
= 0.5 - 0.2 1
(4 - 1.6) 10-2 1
= 12.5 1
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ii) u = Ah 
slope = a
12.5 = 6.25 x 10-4 x
x 10 
=
12.5
6.25 x 10-4 x 10
= 2000kg/m3 
18. i) Q = ml + MC∆ 
Q = 0.006L + 0.006 x 4200 x (100 - 24.4)
Q = 0.006L + 1905.12 
ii) H = MC∆ 
H = 0.4 x 4200 x (24.4 - 15)
H = 15792J ü
iii) 0.006L + 1905.12 = 15792 
0.006L = 15792 - 1905.12
L = 15792 - 1905.12
0.006
= 2.314 x 106Jkg-1 
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232/1,232/2,232/3 physics
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
PHYSICS
Paper 2
July/August 2016
MARKING SCHEME
SECTION A :
1. f = 1  T = 0.008 x 2 = 0.016
T
= 1
0.016 
  = 62.5Hz 
2.
3.
4.
5.
6.
 1 correct lens
 2 mark for each ray
This is due to the deposition of hydrogen gas bubbles (or molecules) on the copper plate / polarization 1
P = VI
I = P = 1000 = 4.167A 1
V
240
The suitable fuse is 5A fuse 1 (give mark for any answer slightly above 4.167A)
P = VI
Efficiency = power output x 100% or
power input
Power input = 100 x 100 1
95
I = 100 x 100
95 x 40
= 2.632A 1
7.
i) positively charged
rod brought near the
cap
ii) electroscope earthed
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232/1,232/2,232/3 physics
8.
9.
iii) Remove earthing then positively charged rod
Electrons are emitted from the surface of the zinc plate 1 causing electrons to move from the electroscope to zinc plate thus
reducing the repulsion force 1
- the dot or spot moves up and down due to the change in direction of the current in the circuit. 1
The movement of the dot is caused by the induced voltage which increases gradually from zero to the peak value and back to
zero on either side causing the beam to move up and down 1
10.
X
N
S
G
Y
1 correct direction (downwards)
11. Alpha forms straight, short and thick tracks while beta forms thin and irregular long tracks 2
12. Used in
- spectroscopy
- detecting forgeries and fresh eggs
- kill bacteria in operating theatres
- skin treatment
1 any one
SECTION B :
13. a) The critical angle of medium is the angle of incidence of a ray of light from the medium to air / vacuum when the angle of
refraction is 90o 1
b) sin  = 1 1
n
sin  = 1
1.5
 = 41.81o 1
c) i) n = sin i, or 3 = sin 70o
sin r
2
sin a 1
sin a = sin 70 x 2 = 0.62645
3
sin a = 0.6265
a = 38.79o 1
ii) n1 sin i1 = n2 sin i2
1.5 sin 38.79 = 4 sin b 1
3
sin b = 1.5 sin 38.79 x 3
4
= 0.7048
b = 44.77o 1
iii) angle c
n1 sin i1 = n2 sin i2
4 sin 44.77o = 1 sin c 1
3
sin c = 0.9390
c = 69.88o
~ 70o 1
14. a) i) Transverse wave 1
The particles vibrate at right angle to the direction of motion of the wave 1
ii)
The wavelength = 50cm or 0.5m 1
iii) v = f 1
f = 9 1
0.5
= 18Hz 1
b) i)
Bright and dark fringes are formed 1
Bright fringes are formed where constructive interference occurs while dark fringes are
formed were destructive interference occurs 1
ii)
Produce coherent sources of light 1
15. a) Image formed
Between F and C
Between F and P
1. Real
1. Virtual
2. Inverted
2. Upright / erect
3. same side as the
3. behind the mirror
object
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1 + 1 = 1 1
u v f
1 + 1 = -1 1
60 v 40
1 = -3 - 2 = -5
v
120 120
v = 24cm 1 same side as the object
c) i)
slope = change y =  (u + v) 1
change x  (uv)
= 62.5 - 40 1
625 - 400
= 0.1 1
ii) since (u + v) = uv
f
then slope = 1
f 1
= 1
0.1 1
= 10cm 1
16. a) Lenz’s law states that the direction of the induced current is such that it opposes the change in magnetic field producing it

b) i) The pointer deflects to and fro from the zero mark 1
This is due to the fact that current on the wire changes direction when moving up and down
ii)
- changing the speed of wire downwards or upwards
- using a stronger or weaker magnetic field (or magnet)
- changing the angle between conductor and magnetic field
c) i)
To reduce energy losses due to eddy currents 1
ii)
To reduce energy loss due to hysteresis
1(during magnetization and demagnetization of the core)
d) Cost = number of units x cost / unit 1
= 3000 x 30 x 60 x 30 x 7 1
1000 x 60 x 60 x 1
= sh.315.00 1
Alt 2
cost = no units x cost / unit
= 3 x 30 x 7 x 30
60
= sh.315.00
17. a) Q - cooling fins 1
R - cathode ray beam 1
b) i) The intensity of X-rays is increased 1 since the number of electrons emitted increases with temperature 1
ii) - harder X-rays are produced 1 higher e.h.t increases the speed (or K.E) of electrons 1 and hence X-rays of
higher energy are produced
c) - tungsten 1
- tungsten has a high melting point 1
d) Voltage = Y-gain x number of division/cm
= 50 x 3.5 1
= 175V 1
= voltage
Resistance
I = V where Re = 2.75 + R1
Re
= 2.75 + 0.8
= 12
= 3.55 1
3.55 1
= 3.380A 1
1 =1 +1 +1
R1 4 2 2
=5
4
R1 = 0.8
ii) V = IR
= 2.75 x 3.38 1
= 9.296V 1
b)
Page | 302
232/1,232/2,232/3 physics
NTIMA, NYAKI AND MUNICIPALITY CLUSTER EVALUATION 2016
PHYSICS
Paper 3
July/August 2016
MARKING SCHEME
PART A
a) d = 2.22cm + 0.10cm 
b) iii)
Volume V of water (cm³) Height, h, of water (cm³)
15
4.2
d)
a)
f)
20
5.4
25
6.7
30
8
35
9.2
40
10.5
1mk each max 5mks + 0.2cm
i) slope = change in y
change in x
= (37.5 - 22.5)cm3  reading off and
(10 - 6)cm
substitution (1mk)
= 3.75cm2  evaluation (1mk)
 units (1mk)
ii) 4s = kd2
k = 4s
d2
k = 4 x 3.75  substitution = 3.044 
PART B
L = 10.2cm + 0.10cm 
i)
x = 6.7cm + 0.50cm 
ii)
k = l = 10.2 = 1.522substitution (1mk)
x 6.7
evaluation(1mk)
iii) Refractive index 1
(2.22)2
2. a) d = 0.36mm + 0.02mm ½
d = 0.00036m ½ + 0.00002m
b) 3.0V 1 + 0.2V
d)
l (m)
0.3
0.4
0.5
0.6
0.7
0.9
V (volts)
0.7
0.9
1.2
1.4
1.65
2.05
I (A)
0.18
0.18
0.18
0.18
.0.18
0.18
3.889
5.00
6.667
7.778
9.167
11.389
NB: values of I should be constant
f) i) slope = y = 11 - 6.5 reading off and
x 0.85 -0.5 substitution (1mk)
= 4.5
0.35  evaluation (1mk)
= 12.86/m  (units(1mk)
ii)
q = 3.142 x (0.00036)2 x 12.86 subst. (1mk)
4
= 0.0000052366
4
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232/1,232/2,232/3 physics
= 0.0000013091
= 1.3091 x 10-6m  evaluation (1mk)
iii) r = E - V
I
= E - IR
I
= 3 - 0.18 x 11.65 substitution 
0.18
= 3 - 2.097
0.18
= 5.017 evaluation  units 
Page | 304
232/1,232/2,232/3 physics
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/1
July/August 2016
Time: 2 hours
SECTION A (25 marks)
Answer ALL the questions in the spaces provided.
1. The water level in a burette is 30.6cm³, 50 drops of water each of volume 0.2cm³ are added to the water in the burette. What is
the final reading of the burette.
(2 marks)
2. Explain why it may be difficult to suck a liquid using a drinking straw on the surface of the moon.
(1 marks)
3. The Fig 1 below shows two identical balloons A and B the balloons were filled with equal amounts of same type of gas. The
balloons are suspended at distance x1 and x2 from a metal cube filled with boiling water and placed on an insulating material.
Metal cube
Fig 1
X1
A
B
Insulated metal
a) State the mode by which heat travels from the cubes to the balloons.
(1 mark)
b) The face of the cube towards A is bright and shiny and face towards B is dull black. State with reasons the adjustments that
should be made on the distances x1 and x2 so that the rate of change of temperature in both balloons remains the same.
(2 marks)
4. Using particulate nature of matter, explain why a solid expands when heated?
(2 marks)
5 . A metal bench feels colder than a wooden one when one sits on both, in a cold morning even though both are at the same
temperature. Explain this observation.
(2 marks)
6. The uniform rod of length one metre shown in the figure below is in equilibrium
T = 30N
Fig 2
X
Pivot
Find the value of X if the weight of the rod is 40N.
7. The springs in the figure below are identical.
(3 marks)
B
A
Fig 3
5N
5N
The extension produced in A is 4cm. Determine the extension is B?
(3 marks)
8 . A lawn sprinkler has 20 holes each of cross-sectional area 1.25 × 10-3 cm² and is connected to a horse-pipe of cross-section
area 2.4cm². If the speed of the water in the horse pipes is 1.5m/s, calculate the speed at which the water emerges from the
holes.
(3 marks)
Page | 305
232/1,232/2,232/3 physics
9. On the axes provided, sketch a graph of Mechanical Advantages (M.A) against load for a pulley system
(1 mark)
M.A
10. The figure below shows a container with small holes at the bottom in which wet clothes have been put. When the container is
whirled air at high speed, it is observed that the clothes dry faster. Fig 4
Holes
Wet cloth
Container
Center of rotation
Fig 4
Explain how the rotation of the container cause the clothes to dry so faster.
(1 mark)
11. A ball rolls off a platform of height 1.8m at a horizontal speed of 15m/s. How far off the edge of the platform does it land?
(Take g = 10ms-2)
(3 marks)
12. State the gas law that relates the volume of a gas to the temperature of the gas.
(1 mark)
SECTION B : (55 marks)
13. The figure 5 below shows a section of ticker-tape produced by a ticker-timer operating frequency of 50Hz.
Fig 5
a) i) Find the average velocity between A and B.
(2 marks)
ii) Find the average velocity between D and E
(2 marks)
iii) Determine the average acceleration.
(2 marks)
b) i) Explain why bodies in circular motion undergo acceleration even when their speed is constant.
(2 marks)
ii)A stone of mass 40g is tied to the end of a string 50cm long and whirled in a vertical circle in 2 rev/s. Calculate the
maximum tension in the string.
(3 marks)
15.a)i) State the Archimedes principle.
(1 mark)
ii)An object weighs 1.05 N in air and 0.66N when fully immersed in water and 0.73N when fully immersed in a liquid. If the
density of water is 1000kgm-3, find the density of the liquid.
(3 marks)
b) i) State the law of floatation.
(1 mark)
ii)The figure 6 below shows a buoy, A, volume 45 litres and mass of 9kg. It is held in position in sea water of density
1.03g/cm by a light cable fixed to the bottom so that 7/8 of the volume of the buoy is below the surface of sea water.
A
Sea water
Cable
Fig 6
Determine the tension, T in the cable.
c) State any two adjustments that can be made to a hydrometer to make it more efficient.
15. a) Distinguish between latent heat of fusion and specific latent of fusion.
(4 marks)
(2 marks)
(1 mark)
Page | 306
232/1,232/2,232/3 physics
b) Figure 7 shows a block of ice. A thin copper wire with two heavy hanging from its ends, passes over the block. The copper
wire is observed to pass through the block of ice without cutting it in a process known as regelation.
Block
of iron
Fig 7
Wooden
Support
Copper
wire
Weights
i)Explain this observation.
(3 marks)
ii) What would be the effect of replacing the copper wire with a cotton thread? Explain.
(2 marks)
c) Figure 8 shows one method of measuring the specific latent heat of fusion of ice. Two funnels A and B contain crushed ice at
0.C
Fig 8
Crushed
ice
Immersion
heater
P=24W
Melted ice
A
B
The mass of melted ice from each funnel is measured after 11 minutes. The result are shown below.
Mass of melted ice in A = 24g
Mass of melted ice in B = 63g
i)What is the reason for setting up funnel A?
(1 mark)
ii) Determine the:
I. Quality of heat supplied by the heater.
(2 marks)
II. Mass of ice melted by the heater.
(1 mark)
III. Specific latent heat of fusion of ice.
(3 marks)
16.a) i) State Newton's second law of motion.
(1 mark)
ii) Explain why a high jumper flexes his knees when landing on the ground.
(1 mark)
b) A ball of mass 100g is dropped from a height 1.25m above the ground surface. It rebounds to a height of 1.1.m.
Calculate
i)Velocity of the ball before impact.
(3 marks)
ii) Force of impact (take g = 10N/kg)
(3 marks)
c) i) Differentiate between elastic and inelastic collision.
(1 mark)
ii) A car of mass 800g collides head on with a truck of mass 5000kg travelling at 40m/s. The car is thrawn on to the bonnet of
the truck which continues to move after impact at 10m/s in the original direction. How fast was the car moving? (3 marks)
17. a) What is meant by absolute zero temperature?
(1 mark)
b) The set up below was used by a group of form three students to verify pressure law.
Bourdon gauge
Thermometer
Dry gas
Heat
Describe briefly how the set-up can be used to verify pressure law.
(4 marks)
c)A 4.5cm³ bubble released at the bottom of a dam measured 18cm³ at the surface of the dam. Work out the depth of the dam
taking atmospheric pressure to be 105 Pa and the density of water as 1g/cm³.
(3 marks)
Page | 307
232/1,232/2,232/3 physics
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
232/2
PHYSICS
Paper 2
(THEORY)
July/August 2016
Time 2 hours
SECTION A : 25 marks)
1. State any two differences between light and cathode rays.
(2 marks)
2. Figure 1 below shows two rays from a mirror forming an image of some object placed in front of the plane mirror. Complete
the ray diagram to show the position of the object.
(2 marks)
I
Fig 1
Eye
3.
energy if it operates at 240V.
(3 marks)
4. Use domain theory to differentiate between magnetic and non-magnetic materials.
(1 mark)
5. State how polarization is reduced in wet Leclanche cell
(1 mark)
6. Light of frequency 5.5 × 1014Hz is made to strike a surface whose work function is 2.5eV. show that photoelectric effect, will
not take place.
(3 marks)
7. State two conditions necessary for electromagnetic induction to occur.
(2 marks)
8. An object is placed 30cm from a concave mirror of focal length 20cm. Calculate the magnification.
(3 marks)
9. You are given three bars. One is magnetized with opposite poles at its ends. Another is magnetized with consequent poles.
The third is not magnetized. Describe an experiment which you would perform to identify each.
(3 marks)
10. The diagram below shows a ray of light xy travelling through a glass block of critical angle 42° to point A.
On the same diagram, draw the path of the ray as it travels past point A.
11. Distinguish between soft and hard x-rays in terms of their production.
12. i) Arrange the following waves in order of increasing frequencies.
Gramma rays, radio waves, infrared, UV and X-rays
ii) Name the electromagnetic radiation used in heating.
SECTION B : (55 marks)
13.a) Distinguish between transverse and longitudinal waves.
b) Figure below shows part of wave profile produced by a vibrator on the surface of water.
(2 marks)
(1 mark)
(1 mark)
(1 mark)
(2 marks)
Displacement (m)
0.6
0.4
0.2
0
-0.2.
0.2
0.4
0.6
0.8
1.0
Time(s)
-0.4
-0.6
Page | 308
232/1,232/2,232/3 physics
Calculate the
i) Period
(1 mark)
ii) Frequency
(1 mark)
iii) Wavelength if velocity of the wave is 330m/s
(3 marks)
c) The diagram below shows a set up that was used to demonstrate that sound requires a material medium for transmission.
Elastic support
Bell jar
Electric bell
Pump plate
To vacuum pump
Give two possible reasons why it is not possible to reduce the sound completely when air is pumped out.
(2 marks)
14.i)The figure below shows a pair a parallel plates of a capacitor connected to a battery, the upper plate is displaced slightly to
the left.
State with reason the effect of this movement on the capacitance.
ii) The figure below shows an electrical circuit with three capacitor X, Y and Z of capacitance
respectively connected to a 24V battery
(2 marks)
8.0 F, 10.0F and 6.0F
X
Z
Determine
I. the combined capacitance of the three capacitors.
II. The charge on the capacitor Z
iii)
The graph below shows the variation of capacitance of a capacitor with voltage supplied across it.
Y
(3 marks)
(2 marks)
Capacitance
-6
(X10 F)
6
3
10
Use the graph to determine the quantity of charge stored in the capacitor.
20 Voltage
(3 marks)
Page | 309
232/1,232/2,232/3 physics
15.a)The diagram below shows an X-ray tube drawn by a student. Use it to answer the questions which follow.
EHT
S
R
Heating
P
Evacuated
State with reason the material used for the part labelled R.
(2 marks)
ii) Why is the tube evacuated.
(1 mark)
iii) How can the wavelength of the X-rays emitted from this tube be reduced.
(1 mark)
b) X-rays are emitted when a tube operates at 3 × 102 V and a current of 0.01 A is passing through it (take e = 1.6 × 10 -19C, Me =
9 × 10-31). Calculate;
i) the velocity of the electron on hitting the target
(3 marks)
ii) the minimum wavelength of the x-rays emitted.
(3 marks)
c) i) State two properties of x-rays.
(2 marks)
ii) State two uses of X-rays.
(2 marks)
16.a) What is meant by the term photoelectric effect.
(1 mark)
b) The figure below shows an arrangement used to investigate photoelectric effect.
Color
White
Filter
Light
X
Y
V
MA
Jockey
(2 marks)
(1 mark)
Stopping potential, Vs(v)
i) Name the parts X and Y
ii) State how the intensity of light affects the photo current.
c) The result obtained from experiment with different colours are shown graphically below.
1.0
0.8
0.6
0.4
0.2
0
1
2
3
4
5
6
7
14
Frequency f(X10 Hz)
Page | 310
232/1,232/2,232/3 physics
From the graph determine;
i) Threshold frequency.
ii) The work function of the metal
17. a) A student connected a circuit as shown below in order to produce a rectified output.
(2 marks)
(3 marks)
D1
A
o
a.c
D2
B
C
R
C.R.O
i) Name the type of rectification shown above
ii) Explain how the rectified output is produced.
iii) What is the purpose of capacitor, C in the circuit.
b) Figure 11 below shows a diffusion cloud chamber for detecting radiation emitted by a radioactive material.
(1 mark)
(3 marks)
(1 mark)
Perspex lid
Transparent lid
Felt ring soaked
in alcohol
Source
Dry ice
Sponge(foam)
Explain how the radiation emitted from the source is detected by the cloud chamber.
(3 marks)
c)A radioactive isotope has a half life of 2.5 hours. How long will it take its activity to fall to 1/8 of its initial level.(3 marks)
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KISII CENTRAL FORM FOUR JOINT EVALUATION
-
Kenya Certificate of Secondary Education
PHYSICS
Paper 3
(PRACTICAL)
July/August 2016
Time 2 ¾ hours
Each candidate should be provided with the following:
Question 1
A metre rule
Two identical 100g masses.
About 200ml of paraffin in 250ml beaker labelled as liquid L.
Three pieces of thread, each about half metre long. The three pieces should be cut from sewing thread.
A stand with clamps
Piece of tissue paper.
A concave mirror of focal length 15 cm with a holder
A screen
A candle
A match box (to be shared)
Question 2
100cm long wire mounted on the mm scale and marked X, (gauge 32) or diameter 0.25mm
80cm long wire marked W of diameter 0.35mm
10 carbon resistor marked R
Centre zero galvanometer
Two Jockeys / Crocodile clips
9 connecting wires 3 of which are atleast 60cm and with crocodile clips at one end.
Micrometer screw gauze (to be shared)(1 for 10 students)
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/3
July/August 2016
Time: 2½ hours
1. This paper has two parts A and B, answer both parts.
PART A
You are provided with the following:
- A meter rule
- Two identical 100g masses
- About 200ml of liquid L in 250ml beaker.
- Stand with clamps
- Tissue paper.
Proceed as follows:
a) Using a stand and one piece of thread, suspend the metre rule in air such that it balances horizontally. Record the position of
the centre of gravity. G.
G = .................................................................... mm
Note: The metre rule should remain suspended at this point throughout the experiment.
b) Set up the apparatus as in figure 1 below.
Fig 1
x
d
Stand
A
Liquid L
B
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232/1,232/2,232/3 physics
Suspend the mass A at a distance x = 50mm. Adjust the position of mass B until it balances mass.
A immersed in liquid L.
Record the distance d, of the mass B from the pivot.
Repeat the same process for other values of x in table 1 below and complete the table.
Table 1
x (mm)
50
100
150
200
250
300
d (mm)
(3 marks)
(5 marks)
c) Plot a graph of d(y-axis) against x
d
x
Stand
A
B
Liquid L
d) Determine the slope, S of the graph.
e) Given S  F where F is the apparent weight of object A in the liquid L and W is the actual weight of
(2 marks)
W
A. Find :i) The value of F.
ii) The upthrust, U
PART B
You are provided with the following.
- A concave mirror with holder.
- A screen
- A meter rule
- A candle
- A match box (to be shared)
Proceed as follows:
f) Set up the apparatus as in figure 2 below.
(2 marks)
(3 marks)
Mirror
Candle
Screen
Fig 2
V
U
g) Put the object at a distance u = 30cm and from the mirror. Adjust the position of the screen until a sharp image is formed on
the screen. Record the distance V
h) Repeat procedure (b) above for the distance u = 40cm and record the new distance V, complete the table 2 below.
Table 2
U(cm)
V (cm)
m=
(m + 1)
30
40
i) Give f 
v
, calculate the values of f hence determine the average value fav ;
m  1
(3 marks)
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QUESTION 2
You have been provided with the following apparatus
- Resistor
- Cell size D new
- Cell holder
- Two resistor wires mounted on mm scales, marked W and X.
a) Proceed as follows.
i) Measure and record the diameter of wire W
D = ......................................................................................... mm
ii) Use the information to calculate the cross-sectional area of the wire. (A)
A = ......................................................................................... mm
iii) Set up the apparatus as shown in the figure below.
l
W
R
Clip1
G
L
Clip(jockey)
X
iv) Move the crocodile clip along W such that the length l = 10cm, then move the jockey to obtain a balance point along the wire
X. Record the length L the value of the balance point along wire X.
b) Repeat steps (iii) for values of l = 20cm, 30, 40, 50, 70 and 80cm and complete the table.
(6 marks)
c) Plot a graph of l cm against
(5 marks)
d) From the graph find the slope S of your graph.
(3 marks)
1
(cm1 )when l = 0
e) From the graph state the value of
(1 mark)
100R Rfind theLvalue of J when R = 10.
f) Given that l
(2 marks)

JL

j
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232/1,232/2,232/3 physics
1.
2.
3.
4.
5.
6.
7.
8.
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/1
July/August - 2016
MARKING SCHEME
= 0.2 × 50 = 10
= 30.6 + 10
= 40.6 cm³
Atmosphere present on surface of moon if very low.
b) Increase the distance x2 since dull black surface emits heat better than the shinny surface.
Molecules of solid absorb heat energy and rate of vibration of molecules increase increasing molecular distance.
Metal bench is better conductor than wooden bench hence conducts a way heat from the body.
Sum of clockwise moment = sum of anticlockwise moments.
0. 5 × 40 = (1 - x) × 3
20 = 30 - 3 x
30z = 10
x = 0.33m
F = ke
k = 5 × 10²== 250N/m
2
A1V1 = A2V2
2.4 × 10-4 × 1.5 = 1.25 × 10-3 × 10-4
9.
M.A
10. When the container at high speed increase the rate of which water drips through the hole results of increase force on the water
drips.
15m/s
11.
S=1/2ut2
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12. The volume of a fixed mass of a gas is directly proportional to its absolute temperature at constant pressure.
13. a)
b) i) The instantaneous velocity change direction therefore there is change in velocity
ii) T  mr 2  mg
max
Tmax  40 102  50 102  (2 )  40 102 10
 8.298N
14.a)
Latent heat of fusion is the quantity of heat required to change any mass of a substance from solid to liquid without
change in temperature ; while specific latent heat of fusion is the quantity of heat required to change a unit mass of a
substance from solid to liquid without change in temperature.
b) i) Copper wire exerts pressure on ice beneath hence ice melts at temperature below the melting point, melted ice flows over
the wire and solidifies its latent heat of fusion is conducted by the wire which melts the ice below and the process continues.
ii) the thread would not cut through the ice block, one the melted ice has solidified its latent heat is not conducted away by
c) i) To determine the mass of ice melted by natural heat / ensure that the ice is dry.
ii) I.
Q = Pt = 24 × 11 × 60 = 15840 J
II.
Mass of ice melted = 63 - 24 = 39g
III. Heat supplied by heater
= heat gained by ice.
15. a)
i) When an object is partly or wholly immersed in a fluid it experience an upthrust equal to the weight of the fluid
displaced.
ii)
Density of liquid = 0.8205×1000=820.5kg/m³
b) i) A floating object displaces its own weight of the fluid in which it floats.
ii) Steel rod sinks because the weight of water it displeases it less than its weight while a ship floats since it displaces water
equal of its weight.
iii) Volume of water displaced = 7 × 0.045 =
8
0.0393765m³
Weight of water displaced
= 0.039375 × 1030 × 10 = 405.5625 kg
Tension = 405.5625 - 90 = 49.44N
c) Increase the size of the bulb
- Increase the length of stem.
16.a)i)
1
 place
 0.in
02the
s direction of force.
The rate of change of momentum is directly proportional to the resultant force andTtake
50
ii) To increase the time of landing to lower reduce the impulsive force.
b) i)
ii) F= ma
= 100 × 10
= 1000N
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232/1,232/2,232/3 physics
c)
i) Elastic collision is one in which bodies bounce off each other after impact while inelastic collision is one in which bodies
stick together after impact.
ii) m1u1 + m2u2 = (m1 + m2) v
800u - 5000 × 40 = 58000 × - 10
u = 1776.5m/s
17. a) The temperature at which the volume of a gas is assumed to be zero.
b)- The temperature of the air is increased in steps by heating the water bath.
- Record the values of pressure and corresponding temperature.
- Draw a graph of pressure against absolute temperature.
- The graph is a straight line through the origin.
c) P1V1 = P2V2
h × 1000 × 10 + 105 × 4.5 × 10-6
= 105× 18× 10-6
h = 135m
Page | 317
232/1,232/2,232/3 physics
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/2
July/August - 2016
MARKING SCHEME
1. Light form of energy which enable us to see while cathode ray are stream of electron.
2.
I
O
Eye
V 2 240  240

 960W
R
60
288000
t
 300s
960
3.
4.
5.
6.
7.
8.
p
Magnetic materials have their domains pointing in the same direction while in non-magnetic materials domains point in
different directions.
Using manganese IV oxide which oxidize hydrogen gas to water.
There must be relative motion between the magnet and coil.
There must be change of flux.
1 1 1
 
f
u v
1
1 1


20 30 v
v  60cm
v 60
m 
2
u 30
9.
i)
1.
Suspend all and let them settle freely. The one that settle in N - S direction is magnetised with opposite poles at the ends.
Use the magnetized bar to identify the other two
10.
A Y
43°
47° 47°
X
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232/1,232/2,232/3 physics
11. Hard X-rays are produced by relatively high potential while soft x-rays are produced by relatively low accelerating potential
12. Radio waves, infrared, UV, X-rays, Gamma rays.
ii) Infra-red.
13.a)
Transverse waves are those whose direction of wave motion in perpendicular to direction of vibration of particles while
longitudinal are those whose direction of wave motion is parallel to direction of vibration of particles.
b) i)
T = 0.4s
ii)
1
1
iii) f 

 2.5 Hz
T

c)
14.i)
0.4
v 330

 132 m
f
2.5
- There is partial vacuum
- Some sound is transmitted by glass.
The capacitance reduces; 1 since the area of overlap is reduced; 1 i.e. C  A
C  C x  C y  8  10  18F
ii) I.
CT 
CCZ
18  6 9


C  CZ 18  6 2
 4.5Fs
II.
Q =CV1
QZ = Total charge in the cct.
QZ = 45 × 10-6 × 24 V 1
III. Q = Area under the graph 1
= ½ × C × V1
= ½ × 6 × 10-6 × 20 1
= 6 × 10-5 C 1
15. a) i) Low work function 1 R - Mixture of metal 1 oxides (barium and strontium)
ii) The tube is evacuated so that electrons do not lose some of their energy through collision with molecules on their way
to the target. 1
iii)
The wavelength of the x-ray emitted is reduced by increasing the heating voltage through the filament 1
b) i)
½ mv² = ev 1
v² = 2er
m
ii)
h = 6.63 × 10-34
c = 1.0328 × 107
e = 1.6 × 10-19
v = 3 × 10²
Page | 319
232/1,232/2,232/3 physics
V 
2  1.6  10 19  3  10 2
9  10 31 ;
9.6  10 17
V 
9  10 31
V  1.0667  10 14
V  1.0328  10 7 ;
6.63  10 31  1.0328  10 7
 min 
1.6  10 19  3  10 2
6.847464  10  27

4.8  10 17
 min  1.4266  10 10 m
c)
i)
ii)
Carry no charge
travel at speed of light
- Crystallography
16.a)
Emission of electrons from surface of metal by shining light on surface of the metal.
b) i)
X - anode
Y - cathode.
ii)
Increase intensity increase the amount of photocurrent.
c) i)
f = 4.5 × 1014 Hz
ii)
17. a) i) Full wave rectification
ii) In the first half cycle A is positive with respect to B, current flows through the diode D1 is forward braised
- In the second half cycle B is positive with respect A, Current flows through D 2 and d forward biased.
- In both cases current flows through the load in the same direction.
iii) Smoothening the wave.
b)- Radiation enters the chamber and ionize air in the chamber.
- Saturated vapour condenses on the ions forming tracks observed through perpex lid.
- The nature of tacks formed can be used to identify the type of radiation emitted.
c) 1 - ½ - ¼ - 1/8
No. of half life = 3
total time - 3 × 2.5 = 7.5 hours.
Page | 320
232/1,232/2,232/3 physics
KISII CENTRAL FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/3
July/August - 2016
MARKING SCHEME
QUESTION 1
Part A
a) G = 500mm
b) Table
x (mm)
c)
50
100
150
200
250
300
d (mm)
46
182
137
181
227
272
Each value of d correct = ½ mark
Total score = 3 marks
Axes - 1 = labelled with units.
Scale - 1 = simple and uniform.
Plotting - 2 = each correctly plotted point = ½ mk maximum score = 2 marks
Line - 1 = straight line with a positive gradient passing through the origin and any other three correctly plotted points.
total marks = 5
d)
e)
272  137
300  150
135

150
 0.9
S
i)
ii)
F
I
F  0.9 N
0.9 
F=W-U
0.9 = 1.0 - U
U = 0.1 N
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232/1,232/2,232/3 physics
PART B
h) Table
U(cm)
V (cm)
M = v/u
(m + 1)
30
26
0.8667
1.8667
40
22
0.55
1.55
Values of V correct - ½ mk each, maximum score - 1makr
Values of m - ½ mk for both
Values of (m + 1) - ½ mk for both
Total marks = 2 marks
i)
26
1.8667
 13.928cm
f1 
22
1.55
 14.194cm
f2 
13.928  14.194
2
 14.06cm
f av 
total marks = 3 marks
Question two
a) i) Diameter of wire W. D = 0.36 × 10-3m 1
ii)
Sub 1 mark
Cal. 1 mark
b) Repeat steps (iii) for values of l = 20cm, 30cm, 40cm, 50cm, 70cm and 80cm and complete the table.
l (cm)
10.0
20.0
30.0
40.0
50.0
70.0
80.0
L (cm)
91.0
1.10
81.0
1.23
73.0
1.37
65.5
1.53
60.0
1.67
55.0
1.96
46.5
2.15
c)
Plot a graph of l cm against

1
cm 1
L

d) From the graph find the slope S of your graph.
S
(5 marks)
(3 marks)
85  20
65

 1.586
2.2  1.23 0.97 10  2
e) From the graph state the value of 1 (cm1 ) when l = 0
x - intercept = 0.94 × 10-2cm-1  correct
f) Given that l 
100 R R
find the value of J when R = 10.

JL
j
y intercept  C 
(1 mark)
(2 marks)
R
 65
J
10
 65
J
10
 0.153
65
Page | 322
232/1,232/2,232/3 physics
KIMA JOINT EVALUATION TEST 2016
Kenya Certificate of Secondary Education
PHYSICS
Paper 1
July/August 2016
Time: 2½ Hours
SECTION A : (25 MARKS)
1. The figure below shows water placed in a measuring cylinder calibrated in cm3
35
30
25
20
15
10
5
0
An object of mass 50.1g and density 16.7g/cm3 is lowered gently in water. Indicate on the diagram the new level. (3 marks)
2. A train of mass 400 tonnes starts from rest and accelerates uniformly at 1.5ms -2. Determine the momentum after moving
400m.
(2 marks)
3. The figure below shows a cone tilted to the left. Explain why the cone will fall to the right when released.
(1 mark)
4. The figure below shows a container with small holes at the bottom in which wet clothes have been put. When the container is
whirled in air at high speed, it is observed that the clothes dry faster.
Motion
Holes
Centre
of rotation
Containers wet clothes
Explain how the rotation of the container causes the clothes to dry so fast.
(2 marks)
5. State the law that relates to the volume of a gas to the temperature of the gas.
(1 mark)
6. The diagram below shows a metal wire structure with a loop of thread inside after it was dipped into a soap solution.
Metal structure
Soap film
Soap film
enclosed
Sketch the appearance of the thread loop after the film enclosed by the thread is broken.
(1 mark)
7. The figure below shows three identical springs each of spring constant K = 75N/m supporting a 20N load. If the connecting
rods weigh 5N.
A
Connecting rod
B
Determine :
C
Page | 323
232/1,232/2,232/3 physics
i)
ii)
8.
9.
the total load supported by the spring B
the total extension produced in the arrangement.
Distinguish between specific heat capacity and heat capacity.
The figure below shows a uniform metre rule pivoted and supported as shown below.
If the mass of the rule is 2.40kg, find the distance X.
(1 mark)
(2 marks0
(2 marks)
(3 marks)
10. The figure below shows a manometer attached to a gas supply. If the atmospheric pressure is 103,360Pa, calculate the
pressure of the gas supply. (Take density of mercury = 13,600kgm -3)
(3 marks)
Atmospheric
pressure
Rubber
Gas
supply
B
10cm
A
Mercury
11. Dust particles in air appear to move randomly, explain this observation.
(2 marks)
12. When a Bunsen burner is lit below wire gauze, it is noted that the flame initially burns below the gauze as shown in the figure
below. After sometime, the flame burns below as well as above the gauze.
Explain this observation.
(2 marks)
SECTION B : (55 MARKS)
13. a) Distinguish between latent heat of fusion and specific latent heat of fusion.
(1 mark)
b) The figure below shows a block of ice. A thin copper wire with two heavy weights hanging from its ends passes over the
block. The copper wire is observed to pass through the block of ice with cutting it in a process known as relegation.
Ice
block
Wooden
block
Copper
wire
Weights
i) Explain this observation.
ii) What would be the effect of replacing the copper wire with a cotton thread ? Explain.
(3 marks)
(2 marks)
Page | 324
232/1,232/2,232/3 physics
c) The figure below shows one method of measuring the specific latent heat of fusion of ice. Two funnels A and B contain
crushed ice at 0oC.
Crushed
ice
P=24W
Melted
ice
A
B
The mass of melted ice from each funnel is measured after 11 minutes. The results are as shown below.
Mass of melted ice in A = 24g
Mass of melted ice in B = 63g
i) What is the reason for setting up funnel A ?
(1 mark)
ii) Determine the :
I. Quantity of heat supplied by the heater
(2 marks)
II. Mass of ice melted by the heater
(1 mark)
III. Specific latent heat of fusion of ice
(3 marks)
14. a) The figure below shows the same metal block weighed in the air, water and liquid. Given that the reading of the level of
water becomes 75cm3 when the metal is fully immersed.
a)
0.82N
0.80N
0.9N
b)
c)
Liquid
Water
Determine :
i) Density of the metal
(3 marks)
ii) Water level before the solid was immersed.
(2 marks)
iii) Explain why the spring balance gives different reading in figure 9(b) and 9(c) with the same metal block. (2 marks)
b) A piece of wood of mass 16g and volume 20cm3 floats on water. What additional mass should be placed on it so that it may
float with its surface level within the surface of water.
(2 marks)
c) i) State one condition of equilibrium for a body acted upon by a number of parallel forces.
(1 mark)
ii) The figure below shows a uniform plant of length 6.0cm acted upon by forces shown. If the plank has a weight of 30N,
determine the weight of W given that volume of metal block is 5000cm3 density of water = 1g/cm3
(4 marks)
1.0m
1m
10N
1m
W
15. a) Figure 4 below shows two identical springs each of spring constant 3N/cm and supporting a load of 30N.
Determine the overall extension of the set up.
b) State two factors that determine the spring constant of a spring.
c) Figure 6 shows a graph of force against extension for a certain spring.
(3 marks)
(2 marks)
Page | 325
232/1,232/2,232/3 physics
12
10
8
6
4
2
0
Fig. 6
2
4
6
8
10
A graph of force against extension
i) On the graph indicate the elastic limit.
(1 mark)
ii)On the same axes, sketch the graph of force against extension for a spring with half the spring constant of the one shown.
(2 marks)
d) A stone of mass 250g falls off the edge of a high platform of height 80cm and lands onto a herical spring of spring constant
20N/m as shown in figure 7 below.
Stone
80cm
Herical spring
ground-level
Determine the length through which the spring is compressed when the stone lands on it.
(3 marks)
16. Figure 8 shows a child of mass 40kg at point A of a fair ground ride. If the velocity of the child at A is 8m/s and the wheel
exhibits uniform circular motion.
C
D
B
6m
A
a)
b)
c)
d)
Determine the velocity of the child at point B.
(2 marks)
Determine the centripetal force acting on the child.
(3 marks)
At which position will the normal reaction of the seat be maximum ? Give a reason for your answer.
(2 marks)
Sketch a graph of gravitational potential energy of the child against height as she moves from point A to point C. On the graph
indicate the values of gravitational potential energy at point A, B and C
Gravitational
potential
energy (J)
Height (m)
Page | 326
232/1,232/2,232/3 physics
17. a) Kinetic theory suggests that the molecules of a gas or a liquid are in a continuous random motion. Explain in terms of the
kinetic theory why a gas exerts pressure which increases when the gas is compressed into a small space.
(3 marks)
b) A gas tube contains enclosed air in the closed end of a horizontal tube of mercury. The length of the trapped air is 150mm
while that of mercury is also 150 mm as shown in figure 8.
150mm
150mm
The other end of the tube is open and the atmospheric pressure is 750mmHg. The temperature is 27 oC. Calculate :
i) The pressure of the enclosed air
(3 marks)
ii) If the tube is raised till its vertical and the open end is facing up, determine the length of the trapped air. (3 marks)
Page | 327
232/1,232/2,232/3 physics
KIMA JOINT EVALUATION TEST 2016
Kenya Certificate of Secondary Education
232/2
......
PHYSICS
Paper 2 (Theory)
July/August 2016
Time: 2½ Hours
SECTION A : (25 MARKS)
1. The experiment below is an equation for a radioactive element A. Elements B and C are the daughter nuclides. A, B and C are
not the actual symbols of any of the elements.
a) Identify the element C
(1 mark)
b) State two of its characteristics.
(2 marks)
2. i) State the characteristics of images formed by a pinhole camera.
(2 marks)
ii) What is the effects on the image when the camera is elongated ?
(1 mark)
3. The figure below shows the object O and its image O 1 formed by a concave mirror. Locate the position of the principle focus.
(2 marks)
O1
O
4. An electromagnet is made by winding insulated copper wire on an iron core. State three changes that could be made to
increase the strength of the electromagnet.
(3 marks)
5. Figure below shows a U-shaped magnet stored with a keeper.
Keeper
Explain how this method helps to retain magnetism longer.
(2 marks)
6. State the energy transformation when fast moving electrons are suddenly stopped by a target in an X-ray tube.
(1 mark)
7. A current of 13A flows through a heating element of resistance 8.5 for 1.5 minutes. Calculate the quantity of heat supplied.
(3 marks)
8. Give a reason why it is not advisable to smoke a cigarette near a charging battery.
(1 mark)
9. State the dynamo rule.
(1 mark)
10. Radio X is broadcast on wavelength 150m at a frequency of 200KHz. Calculate the velocity of the radio waves. (2 marks)
11. Draw a diagram to illustrate the correction of myopia.
(1 mark)
12. The figure below shows the displacement of a spot on a cathode ray oscilloscope screen.
B
3cm
A
The spot appears on the CRO at position A. When DC voltage is applied to Y-plates the spot is displaced to position B. The Ygain is set at 20V/cm.
i) State the type of voltage applied.
(1 mark)
ii) Find the voltage applied.
(2 marks)
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232/1,232/2,232/3 physics
SECTION B : (55 MARKS)
Answer all the questions from this section in the spaces provided.
13. The figure below shows a simple form of an a.c generator.
B
C
N A
S
D
P
X
Q
Lamp
Y
a) Name the parts P and Q
(2 marks)
b) State the functions of P and Q
(1 mark)
c) State two ways of increasing the e.m.f produced by this apparatus.
(2 marks)
d) Which terminals X and Y is positive if the coil is rotating in the direction shown ?
(1 mark)
e) State one use of electricity where it is essential to use a direct current. How will you modify the above apparatus to obtain a d.c
output ?
(2 marks)
f) Differentiate between a generator and a motor.
(2 marks)
14. a) i) State the basic law of electrostatics.
(1 mark)
ii) In testing for the sign of charge on a body, explain the behaviour of a positively charged electroscope when charged bodies are
brought closer to the electroscope.
(2 marks)
b) The figure below shows an arrangement which may be used to charge a capacitor of capacitance 50F and then to connect it to
a capacitor of capacitance 20F.
A SB
12V
50 f
C1
20 f
C2
i) The switch S is first placed at position A, so that the capacitor C is connected to the 12V dc supply. Calculate the charge stored
in the capacitor.
(3 marks)
ii) The switch S is now changed to position B. Calculate the final potential difference across the capacitors.
(3 marks)
15. a) Explain what is meant by P-N junction diode.
(1 mark)
b)The circuit diagram in the figure below is used to measure the current for various values of voltage across identical diodes P
and Q.
A
P
Q
V
Voltage
R1
R2
X Y
What is the purpose of the resistor R1 ?
(1 mark)
ii) Sketch the graph on the same axes to show the results of the experiment when the switch is in the and Y.
(2 marks)
iii) The d.c supply is replaced with an a.c supply and a CRO is connected across R 2. Sketch the trace observed on the screen.
(2 marks)
16. The figure below shows a ray of white light dispersed in a triangular prism. The speed of violet light in the prism is 1.88 x
Screen
108m/s.
Glass prism
White light 
r
R
V
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232/1,232/2,232/3 physics
a) Explain how glass disperses white light into read and violet bands.
(1 mark)
b) Determine the refractive index of the prism material for violet light. (Take speed of violet light in vacuum = 3.0 x 10 8m/s)
(3 marks)
c) Show on the figure the critical angle, c, for violet light and determine its value.
(3 marks)
d) Given that r = 21.5o determine the angel .
(3 marks)
e) On the same figure, sketch the part of red light after white light strikes the prism if the prism was replaced by another of
similar shape but lower refractive index. (use dotted line for the answer)
(2 marks)
17. Study the circuit below and answer the following questions.
2V
6
3
2.5
6
a) Calculate the effective resistance of the circuit.
(3 marks)
b) Determine the current flows through 3W resistor.
(4 marks)
c) When a candle flame is brought near the cup of charged electroscope, the electroscope discharges. Explain this observation.
(2 marks)
d) Define the term capacitance.
(1 mark)
18. a) The figure below shows an X-ray tube.
E.H.T
Vacuum
B
A
cathode
i) Name the parts labelled A and B
(2 marks)
ii) Suggest with a reason the material used for A
(1 mark)
iii) State the reason why the X-ray tube is evacuated.
(1 mark)
iv) For the X-ray tube, how would the following be controlled
a) The intensity
(1 mark)
b) Quality of X-ray
(1 mark)
b) A potential difference of 50KV is applied across CRO tube. Given that the charge of an electrons
e = 1.6 x 10-19C and the mass of the electron Me = 9.1 x 10 -31kg. Calculate the kinetic energy of the electrons.
(3 marks)
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232/1,232/2,232/3 physics
KIMA JOINT EVALUATION TEST
PHYSICS
Paper 3
July/August 2016
CONFIDENTIAL INSTRUCTIONS
Each student to be provided with :
Question 1
- three new size D dry cells (Eveready Red)
- cell holder (3 cell)
- 2200F capacitor, labelled C
- stop watch
- six connecting wires at least 4 with crocodile clips
- a switch
- 4 kilo -ohm carbon resistor (Or a set of resistors whose resistance is 4K) labelled R
- an analogue voltmeter (0 - 5V range)
- a metre rule
- convex lens (f = 15.0cm)
- lens holder
- candle
- a white screen
Question 2
- candle wax (cut into small pieces)
- water bath (to be shared)
- stop watch
- boiling tube
- thermometer
- cork with a hole or cardboard with hole
- water
- tripod stand
- tube holder
- 50g mass labelled M
- complete stand
- 100g mass labelled N
- plastic beaker, 250ml
KIMA JOINT EVALUATION TEST 2016
PHYSICS
Paper 3
July/August 2016
Time: 2½ Hours
1. PART A
You are provided with the following :
- an analogue voltmeter (0 - 5V range)
- a 4 kilo ohm carbon resistor (or a set of resistors whose resistance is 4KW, labelled R
- three new size D dry cells
- three cells holders
- a 2200F capacitor labelled C
- a stopwatch
- six connecting wires at least four of which have crocodile clips
- a switch
Proceed as follows :
i) Connect the circuit as shown in figure 1 below.
Switch(open)
E
R
C
+
-
V
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232/1,232/2,232/3 physics
ii) Close the switch and note the maximum voltage attained on the voltmeter. Record it as V max
Vmax = .......................................................... volts
(1 mark)
iii) Open the switch and simultaneously start your stopwatch and note the time taken for the voltmeter reading to increase from
zero to the value of voltage indicated in the table. Each time short the terminals of the capacitor to attain zero volts on the
voltmeter before repeating each step. Complete the table 1 below.
Table 1
Voltage, V (volts)
Time (t) for voltage to increase from zero to V t(s)
0
1.0
1.5
2.0
2.2
iv) On the axes below, plot a graph of voltage, V against time, t.
v) Determine the slope of the graph at which V = Vmax
2
vi) Determine the resistance R of the voltmeter given that t = 0.693CR where t is the time at which
V = Vmax and C is the capacitance of the capacitor.
2
PART B
You are provided with the following :
- a metre rule
- a convex lens
- a lens holder
- a candle
- a white screen
Proceed as follows :
i) Set up your apparatus as shown in figure 2 below.
2.5
(5 marks)
(3 marks)
(2 marks)
L cm
V cm
Metre rule
Candle
Lens
at 40cm mark
Bench
ii) The position of the lens should be at 40cm mark.
iii) Set the candle at a distance L = 80cm from the screen. Move the lens away from the candle until a sharp image of the candle is
seen on the screen. Measure the distance V1 between the screen and the lens.
V1 = ......................................................................... cm
(1 mark)
iv) Repeat steps (i), (ii) and (iii) above but this time move the lens from the 40cm mark towards the candle and measure the
distance V2 between the screen and the lens.
V2 = ........................................................................ cm
(1 mark)
–
v) Determine the focal length, f of the lens from F=
(2 marks)
2.
PART A
You are provided with the following apparatus :
- candle wax
- source of heat
- stop watch
- boiling tube
- thermometer
- cork with a hole or cardboard with hole
- water
- tripod stand
- tube holder
Proceed as follows :
i) Heat the water in the beaker until it starts to boil.
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232/1,232/2,232/3 physics
ii) Place some candle wax in the boiling tube and heat the wax indirectly using the boiling water in beaker as shown in figure 3
below.
Boiling tube
Boiling water
Melting candle wax
gauze
Heat
iii) When the wax has completely melted, continue heating for about two minutes. Meanwhile insert the thermometer in the
boiling tube through the hole in cork or cardboard. Adjust the thermometer until the bulb of the thermometer is completely
immersed in melted wax.
Thermometer
Cork or cardboard
Boiling tube
Boiling water
Melting candle wax
gauze
Heat
Continue heating until the thermometer records no further change in temperature. This is the maximum temperature reached.
Record this temperature, as T max.
Tmax = .............................................................. oC
(1 mark)
iv) Now remove the boiling tube from the boiling water and simultaneously start the stopwatch. Record the temperature of the
cooling wax at intervals of two minutes. Record and complete
Table 2 below.
Time (min)
0
Temperature (°C)
2
4
6
9
11
14
(7 marks)
v) In the axes below, plot a graph of temperature, oC against time, t
(4 marks)
vi) Determine the rate of cooling at t = 5 min.
(2 marks)
PART 2
You are provided with the following :
- a metre rule
- a complete stand
- a 50g mass labelled M and a 100g mass labelled N
- some water in a beaker
Proceed as follows :
a) Balance the metre rule with a thread from the clamp and record the point of C.O.G at balance point.
C.O.G ............................................................................ cm mark.
(1 mark)
(NB: For the rest of this experiment the thread should be maintained at the point of C.O.G)
b) Set up the apparatus as shown in figure 5 below. Use the thread provided along to hang the masses such that the positions of
support can be supported.
c) Adjust the position of the 100g mass such that the system is again balanced when the 50g mass is wholly submerged. Note and
record the distances D and x.
x = .................................................... cm
(1 mark)
D = ....................................................... cm
(1 mark)
d) Using the principle of moments determine the weight W 1 of the 50g mass in water and hence determine the upthrust U w in
water.
W1 = .............................................................................................................................. .......................
(2 marks)
Ww = ....................................................................................................................................................
(1 mark)
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232/1,232/2,232/3 physics
KIMA JOINT EVALUATION TEST 2016
PHYSICS
Paper 1
July/August 2016
MARKING SCHEME
1.
2.
3.
4.
5.
6.
7.
𝝆
v = 50.1 = 3cm3
16.7
Indicating the new level on the diagram (13cm3)
V2 = u2 + 2as
= 0 + 2 x 1.5 x 400
V = (3 x 400)m/s = 34.641m/s
Momentum = mass x velocity
= 400 x 103kg x 34.641m/s
= 1.3856 x 107kgm/s
The moment of the weight of the cone is towards the right (clockwise direction)
The water is expelled through the holes when the container is rotated at high speed
For a fixed mass of a gas, volume is directly proportional to the absolute temperature at constant pressure
i)
20N = 10N
2
ii) Extension of A = F = 20 + 5 = 0.333M
k
75
Extension of B and C = F = 20 = 0.133
2k 150
Total extension = 0.333 + 0.133
= 0.467M
8. Heat capacity - amount of heat required to raise the temperature of a body by one Kelvin
Specific heat capacity - amount of heat required to raise the temperature of 1kg of a substance by 1 Kelvin
9. Sum of clockwise moments = sum of anticlockwise moments
24 x 0.5m = 16 x (1 - x)
12 = 16 - 16x
16x = 16 - 12 = 4
x = 4 = 0.25M = 25cm
16
10. Gas pressure = hdg x atm. pressure
= (0.1 x 13600 x 10) + 103360
= 116960Pa
11. Dust particles collide with invisible air particles that also move randomly
12. Wire gauze is a good conductor of heat hence conducts heat away from the region. The gas reaches its ignition temperature
late when the flame starts showing on the upper region
13. a) Specific latent heat of fusion is per unit mass but latent heat of fusion is for any mass
b) i) Pressure lower melting point and when
the wire passes through the ice refreezes back. Ultimately the wire goes
through
ii) The cotton thread will not cut through the ice block at all since it is a poor conductor of heat
c) i) As a control experiment
ii)I. Q = Pt
= 24W x (11 x 60)s
= 15840J
II.
M = (63 - 24)g
= 39g
III. Q = MLf
Lf = Q
M
= 15840J = 406153.85Jkg-1
Page | 334
232/1,232/2,232/3 physics
(
14. a)
b)
c)
iii)
b)
15. a)
b)
c)
)
R.D =
weight in air
loss in weight in water
= 0.9
0.1
=9
Density of solid
= 1000 x 9
= 9000kg/m3 1
Water level before solid was immersed
= 75 - volume of solid 1
Volume of solid = u
pg
= 0.9 x 100 x 100 x 100
9000 x 10
New level = 75 - 10.0 = 65cm3 1
i)
The liquid has lower density 1 hence less up thrust, 1 is experienced
ii)
= upthrust when fully 1immersed - its weight 1
=
20
x 1,000 x 10 - 0.16
1000,000
0.20 - 0.16
= 0.04N 2
a) Net force on the body equals to zero 1
Sum of clockwise moment = sum of anticlockwise
30 x 2 + 10 x 3 = F x 4 1
F = 30 x 2 + 10 x 3
4
= 22.5N 2
KT = K1 + K2 (in parallel)
= (3 + 3)N/cm
= 6N/cm
F = KT T
30N = 6N/cm x T
 T =30N
6N/cm
= 5cm
- nature of wire used
- Diameter of spring
- Length of spring
i)
ii)
Elastic limit
Force
(N)
second spring
Extension
d) Gravitational PE = Elastic PE
mgh = ½ke2
250 x 10 x 80 = ½ x 20 x e2
1000
100
 2 = 10e2
10 10
 e2 = 0.2
e = 0.2
= 0.4472m
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232/1,232/2,232/3 physics
16. a) 8m/s - remain constant 2
b) FC = mv2 1
r
= 40 x 82 1
3.0
8.53N 1
c) A


mv 2
 T 
 mg 
r


17. a)
- a gas is in a state of continuous random
motion
- Collisions of gas with wall exerts pressure
- When volume of gas decreases, number of collisions per second increase exerting more pressure
b) i) Pair = Patmospheric
= 750mmHg
ii)
P2 of gas = Pa + h g due to thread
= 750mmHg + 150mmHg
= 900mmHg
Pa
150mm
P2
= P1V1 = P2V2
T1
T2
 P1l1 = P2l2
T1
T2
= 750 x 150 = 900 x l2
300
300
But volume, v  length of air column
T1 = T2 = constant
 l2 = 116.67mm
Page | 336
232/1,232/2,232/3 physics
1.
2.
KIMA JOINT EVALUATION TEST 2016
PHYSICS
Paper 2
July/August 2016
MARKING SCHEME
-  particle
- positively charged
- slow moving because they are massive
- high ionizing effect
i) - real
- inverted
ii) The size of the image increases
3.
4.
- increase the current
- increase the number of turns per unit length / increase windings
- use of a U-shaped core
5. - the keeper is magnetized
- this makes the dipoles to form a closed loop
6. K.E  heat + X-rays
7. E = I2RT
= 132 x 8.5 x 1.5 x 60
= 1.293 x 105J
8. To avoid explosion because of the hydrogen gas produced during charging
9. When the thumb, forefinger (first finger) and a second finger of the right hand are held mutually at right angles with the
forefinger points to the direction of the field, the thumb points to the direction of motion and the second finger points to the
direction of induced current.
10. V = f1
= 200,000 x 1500
= 30,000,000m/s
= 3.0 x 108m/s 1
11.
Biconcave
Lens
12. a) Constant voltage 1
b) 3 x 20 1
= 60V 1
13. a) P - slip rings or commutators
Q - carbon brushes
b) P - to relay induced e.m.f to the carbon brushes
- to produce a.c current / e.m.f from the loop
Q - to tap the induced e.m.f from the coil and relay to outer circuits
c) - increasing number of loops rotating in magnetic field
- increasing speed of rotation of coil
- increasing strength of magnetic field
d) X - positive
Y - negative
- use split ring / commutator halves instead of slip rings
f) generator motor
- converts mechanical - converts electrical to
- energy to electrical mechanical
14. a) i) unlike charges attract like charges repel
ii) - for a positively charged rod the leaf diverges
Page | 337
232/1,232/2,232/3 physics
- for a negatively charged rod the leaf divergence decreases
b) i) Charge - voltage x capacitance 1
Q = CV
= 12 x 50mF 1
= 600MC or 6 x 10-4C 1
ii) Total charge = 6 x 10-4C
QT = C1V + C2V 1
Where V is voltage across both capacitors in parallel
6 x 10-4 = 5 x 10-5 + 2 x 10-5V 1
6 x 10-4 = 7 x 10-5V
V = 8.57V 1
15. a) A solid state material made of a group IV element half of which doped with a
doped with a trivalent impurity
b) i) To vary the resistance and hence the voltage across R2 and the diodes
pentavalent impurity and the other half
ii)
Voltage
Switch at X and Y
iii)
16. a) Red and violet lights travel at different velocities in glass leading to separation
b) R.I, = velocity in vacuum
velocity in prism
= 3.0 x 108m/s
1.88 x 108m/s
= 1.6
Screen
c)

r
C
R
check for correct C
sin e = 1
n
= 1 = 0.625
1.6
C = sin-1 0.625
= 38.68o
= sin 
sin r
1.6 =
sin 
sin 21.5o
-1
 = sin (1.6 x sin 21.5o)
= 35.90o
Check the answer in (c) above (r increases
V
d) n
e)
in size)
Page | 338
232/1,232/2,232/3 physics
17. a)
 b)
 
c)
d)
18. i)
ii)
iii)
iv)
1 =1+1+1 =1+2+1=4
RT 6 3 6
6
6
(parallel arrangements)
RT = 6 = 1.5W
4
series = R1 + R2
= 1.5 + 2.5 
= 4 
V = IR
I = V = 2 = 0.5A 
R 4
p.d across 2.5 resistor
= 0.5 x 2.5
= 1.25V 
pd across parallel resistors
= 2.0 - 1.25
= 0.75V 
I = V = 0.75
R 3
= 0.25A 
The flame ionizes air producing positive and negative ions. These are attracted to the cap of the electroscope causing
discharge
Is charge stored per unit voltage
A - target (metal ) 
B - anode 
Tungsten / molybdenum - high melting point & high b.p
To avoid ionization - losing energy during collision with some other ions
a) Varying the heater current
b) Varying the accelerating potential (E.H.T)
b) K.E = ½mev2 = eV
= 1.6 x 10-19 x 5.0 x 104 
= 8.0 x 10-15J 
Page | 339
232/1,232/2,232/3 physics
KIMA JOINT EVALUATION TEST 2016
PHYSICS
Paper 3
July/August 2016
MARKING SCHEME
1. PART A
ii) Vmax = 2.7 volts
iv)
voltage, V (volts)
0.0
0.5
2.
Time (t) for voltage to increase to V 0.00
2.23
v)Graph of voltage against time
vi)
Slope at V = 0.85 volts
slope = V
t
= 29 x 0.02 1
14 x 0.25 1
= 0.58
3.5
= 0.1657V/s 1
vii)
t = 0.693CR
3.0 = 0.693 x 2200 x 10-6R 1
R=
3.0
0.693 x 2200 x 10-6
= 3.0
1.5246 x 10-3
= 1967.7292 1
PART B
The convex lens f = 15cm + 2.0cm
iii) V1 = 25.0cm + 1.0cm
iv) V2 = 57.0cm + 1.0cm
v) f = 802 - (57 - 25)2
4 x 80
= 16.8cm
PART A
iii) Imax = 93.0oC + 1oC
iv)
Time, t (min) 0
Temp. °C 93.0
2
69.0
4
63.0
6
58.0
1.0
1.2
1.4
1.6
4.37
6.91
9.22
19.19
9
56.0
11
54.0
14
53.0
v) graph
Page | 340
232/1,232/2,232/3 physics
vi) Rate of cooling at 5min = grad. of tangent
= 
t
= 69 - 50
0 8.9
= 2.134oC/min
PART B
a) C.O.G = 50.0cm (49.5 - 50.5cm)
c) x = 20.0cm
D = 45.0cm
d) W1 = ?
W1D = x x 1.0
 W1 = 20 x 1
45
= 0.44N
Uw = 0.5 - 0.44
= 0.06N
V = Vmax = 1.7
2
2
at that point
Page | 341
232/1,232/2,232/3 physics
BURETI SUB-COUNTY JOINT EVALUATION TEST
Kenya Certificate of Secondary Education
232/1
PHYSICS
Paper 1
July/August 2016
Time: 2 Hours
SECTION A : (25 MARKS)
1. The water level in a burette is 20.3cm3. 50 drops of water each of volume 0.1cm3 are added to the water in the burette. What
is the final reading of the burette?
(2 marks)
2. The springs in figure 1 are identical.
Fig. 1
3.
4.
The extension produced in A is 4cm. What is the extension in B?
(3 marks)
Water flows through a narrow pipe of radius 6cm connected to another pipe of radius 9cm. If the speed of water in the narrow
pipe is 3m/s, determine the speed of water in the wider section.
(3 marks)
Figure 2 shows a marble placed on an inverted bowl.
Fig. 2
5.
State and explain the type of equilibrium the marble is.
A uniform meter rule is balanced as shown in the figure 3 below.
(3 marks)
Fig. 3
6.
By displacement method, the immersed object is found to occupy 13.5cm 3. Determine the density of the liquid in SI units.(3
marks)
Figure 4 below shows a thermometer used by a doctor to determine the temperature of a patient. Why is it difficult to work
with this thermometer?
(2 marks)
Fig. 4
7.
Figure 5 shows two identical thermometers. Thermometer A has a blackened bulb while thermometer B has a silvery bulb. A
candle is placed equidistant between the two thermometers.
Fig. 5
Page | 342
232/1,232/2,232/3 physics
State with a reason the observations made after sometime.
(2 marks)
8. When a liquid is heated in a glass flask its level at first falls then falls then rises. Explain this observation.
(2 marks)
9. Sketch a graph showing how volume of pure water varies with temperature from0 o to 10oC.
(2 marks)
10. A tall building has two barometers, one at the ground floor reading 750mmHg and the other at the top reading 748mmHg.
Determine the height of the building.
(2 marks)
11. What does study of thermodynamics entails?
(1 mark)
SECTION B: (55 MARKS)
12. a) State what is meant by an ideal gas.
(1 mark)
b) The pressure acting in a gas in a container was changed steadily while the temperature of the gas as maintained
constant. The value of volume V of the gas measured for various values of pressure. The graph in the figure 6 shows the
relation between the pressure, P1 and the reciprocal of volume 1/V
Fig. 6
i) Suggest how the temperature of the gas could be kept constant.
(1 mark)
ii) Given that the relation between the pressure P1 and the volume V1 of the gas is given by PV = k. Where k is a constant,
use the graph to determine the value of k.
(3 marks)
iii) What physical quantity does k represent?
(1 mark)
iv) State one precaution you would take when performing such an experiment.
(1 mark)
c) A gas occupies a volume of 4000 litres temperature of 37 oC and normal atmosphere pressure.
Determine the new volume of the gas if it is heated at constant pressure to a temperature of 67 oC
(normal atmosphere pressure P = 1.01 x 10 5Pa)
(4marks)
13. Figure 7 below shows an inclined plane, a trolley of mass 30kg is pulled up a slope by a force of 100N parallel to the slope.
The trolley moves so that the centre of mass C travels from points A to B.
i) What is the work done on the trolley against the gravitational force in moving from A to B?
ii) Determine the work done by the force in moving the trolley from A to B
iii) Determine the efficiency of the system.
iv) Determine the work done in overcoming the frictional force.
v) Determine the mechanical advantage of the system.
(2 marks)
(3 marks)
(1 mark)
(3 marks)
Page | 343
232/1,232/2,232/3 physics
14. a) Figure 8 below is a graph showing the velocity of a body plotted against time.
Fig. 8
i) Describe the motion of the boy over :
(3 marks)
CD, DE,EF
ii) What is the acceleration of the body over the region AB?
(1 mark)
iii) What is the average velocity over the total journey?
(2 marks)
b) Figure 9 below shows a trolley moving on a circular rail with a vertical plane, given that the mass of the trolley is 250g
and the radius of the rail is 1.6m.
Fig. 9
i) Determine the minimum velocity at which trolley passes point X.
(3 marks)
ii) Find the angular velocity at point Z
(3 marks)
iii) The force exerted on the rail at this point.
(2 marks)
15. a) A boy throws a tennis ball vertically upwards from a truck moving at a constant velocity. Give the reason why the ball
lands back exactly the same point where it was projected. (1 mark)
b) Define impulse in terms of momentum.
(1 mark)
c) A trailer of mass 30 tonnes travelling at a velocity of 72km/h runs onto a stationary bus of mass 10 tonnes.The
impact
takes 0.5 seconds before the two vehicles move off together at a constant velocity for 15 seconds. Determine:
i) The common velocity
(3 marks)
ii) The distance moved after the impact.
(2 marks)
iii) The impulsive force on the trailer on impact.
(3 marks)
d) Give a reason why when a passenger jumps from a floating boat, the boat moves backwards.
16. Figure 10 below shows a buoy B of volume 40 litres and mass 10kg. It is held in position in sea water of density 1.04gcm -3 by
a light cable fixed to the bottom so that 3/4 of the volume is below the surface of the sea water.
Fig. 10
i) Show all the forces acting on the buoy at equilibrium.
ii) Determine the tension in the cable.
c)Figure 11 shows a bulb hydrometer.
Fig. 13
i) State the principle in the hydrometer.
ii) Explain why the hydrometer has a weighted bulb and narrow stem.
(3 marks)
(3 marks)
(1 mark)
(1 mark)
Page | 344
232/1,232/2,232/3 physics
BURETI SUB-COUNTY JOINT EVALUATION TEST
Kenya Certificate of Secondary Education
232/2
PHYSICS
Paper 2
July/August 2016
Time: 2 Hours
SECTION A : (25 MARKS)
Answer all the questions in this section in the spaces provided.
1. A current carrying wire is placed above a compass needle as shown in the figure below.
If the current flows in the direction A to B, show in the diagram the deflection of the compass needle.
(1mark)
2. State two differences between sound waves and microwaves.
(2 marks)
3. The figure below shows a highly positively charged rod being moved slowly downwards towards the cap of a negatively
charged leaf electroscope. It is observed that the leaf initially falls then rises.
Explain this observation.
4. A soft iron bar AB is placed in a magnetic field of a horse shoe magnet as shown below.
(2 marks)
What are the polarities of A and B.
(1 mark)
5. A certain car battery is rated 30Ah. Determine the amount of current it can supply in 10 minutes.
6. A coin is placed at the bottom of a beaker filled with water to a height of 2.4cm as shown in the figure below. Given that the
refractive index of water is 1.33, determine the apparent depth of the coin.
(3 marks)
Page | 345
232/1,232/2,232/3 physics
7. The figure below shows water waves travelling from region A through B to C in a ripple tank.
On the same diagram, complete the figure to show incident waves at region A and after crossing the boundary to C.(2 marks)
8. The figure below shows part of an electric circuit. The charge stored in the 9 F capacitor is 1.4 micro coulombs C)
Determine the p.d across the 5 F capacitor.(3
(marks)
9. The figure below shows an image I formed by an object placed infront of a convex mirror. C and F are the centre of curvature
and principal focus of the mirror respectively. Using appropriate rays locate the object position.
(3 marks)
10. Given that the wavelength of a certain electromagnetic wave is 7500cm, determine its frequency. (Take the speed of light in a
vacuum as 3.0 x 108m/s)
(2 marks)
11. Uranium -234 undergoes a radioactive decay represented by the equation shown below.
Find the value of a and b
(2 marks)
12. State two modifications that can be done to a pinhole camera in order to be used to fake still photographs.
(2 marks)
SECTION B : (55 MARKS)
Answer all the questions in the spaces provided.
13. a) State the Faraday’s law of electromagnetic induction.
(1 mark)
b)i) A transformer is connected to an a.c source of 240V to deliver 12A at 120V to a heating coil. If 20% of energy taken
from the supply is dissipated in the transformer, calculate the current in the primary coil.
(4 marks)
ii) If the wire in the primary coil is charged to have a
determine the power dissipated as heat in the coil.
(2 marks)
c) A house has three rooms each with two 240V, 60W bulbs. If the bulbs are switched on from 7.00p.m to 10.00pm daily.
i) Calculate the power consumed per day in kilowatt-hours.
(3 marks)
ii) Find the cost per week for lighting these rooms at sh.6.30 per kilowatt hour.
(2 marks)
d) What is the purpose of earthing in domestic wiring circuit?
(1 mark)
14. a) The distance of separation between the plates of a certain capacitor is reduced. State how this affects the capacitance of a
capacitor.
(1 mark)
b) You are provided with the following apparatus used for studying charging of a capacitor.
An uncharged capacitor, voltmeter, milliameter, 6V battery, connecting wires, a switch and a load resistor R.
i) Draw a circuit diagram that can be used to charge the capacitor.
(2 marks)
ii) Use the circuit diagram drawn above to explain how the capacitor gets charged.
(3 marks)
iii) State the purpose of resistor R.
(1 mark)
Page | 346
232/1,232/2,232/3 physics
c) The zinc plate shown below is connected to a negatively charged electroscope and is exposed to
i) Explain what happens to the leaf of the charged electroscope.
ii) If the same experiment is repeated using a positively charged electroscope, explain the observation.
15. a) Differentiate between X-rays and cathode rays in their mode of production.
b) The figure below shows a cathode ray oscilloscope (CRO) drawn by a student.
(3 marks)
(3 marks)
(2 marks)
i) Identify two mistakes in the diagram.
(2 marks)
ii) In a correctly drawn C.R.O, what adjustment can be made to obtain a very bright spot.
(1 mark)
ii) State the reason why the fluorescent screen should be earthed.
(1 mark)
iv) State two differences between a C.R.O and T.V tube.
(2 marks)
c) In an X-ray tube, the accelerating voltage is 100KV
i) Calculate the kinetic energy of the electrons arriving at the target (take e = 1.6 x 10-19C)
(3 marks)
ii) If 0.5% of the kinetic energy is converted to X-rays, determine the minimum wavelength of the emitted X-rays (take h =
6.63 x 10-34Js and C = 3.0 x 108m/s)
(4 marks)
16. a) State one condition necessary for Ohm’s law to be obeyed.
(1 mark)
b) The figure below shows a battery of e.m.f 12V and internal resistance of
connected to resistors and an ammeter.
i) Determine the ammeter reading when the switch S, is open.
ii) Find the ammeter reading when the switch is closed.
c) A lens forms an image on a screen when the distance between the object and the lens is 100cm.
i) What kind of lens was used? Explain.
ii) If the size of the image is twice the size of the object, determine the distance of the image from the lens.
iii) Determine the power of the lens.
(3marks)
(4 marks)
(2 marks)
(2 marks)
(2 marks)
Page | 347
232/1,232/2,232/3 physics
BURETI SUB-COUNTY JOINT EVALUATION TEST
232/3
PHYSICS
Paper 3
July/August 2016
Time: 2½ Hours
1. You are provided with the following apparatus :
one resistor labelled R = 40
- a wire labelled W mounted on milliameter scale
- a wire labelled S mounted on a milliameter scale
one dry cell and a cell holder
one jockey
- one centre zero galvanometer
- eight connecting wires, four with crocodile clips at both ends
- a micrometer screw gauge
- a switch
Proceed as follows
a) Determine the average diameter D, of the wire labelled W using the micrometer screws gauge provided.
D1 = ............................................................ mm
D2 = ............................................................. mm
(½ mark)
(½ mark)
D = D1 + D 2
2
(½ mark)
b) Set up the apparatus as shown in the circuit diagram in figure 1 below.
Use the crocodile clips to fix length L, of wire labelled S at 50cm from the end connected to the galvanometer G.
c) Close the switch and use the jockey to touch one end of the wire W, and then the other end. The deflections on the
galvanometer should be in opposite directions, if not check the circuit. Adjust the positions of the jockey along the wire W
until there is no deflection in the galvanometer. Record the value of x and y.
x = ..................................................................... cm
(½ mark)
y = .................................................................... cm
(½ mark)
d) Record for other values of L in the table.
L (cm)
45
40
35
30
25
20
X (cm)
Y (cm)
(3 marks)
Page | 348
232/1,232/2,232/3 physics
e) i)Plot a graph of y/x (y-axis) against L.
Fig. 2
ii) Determine the slope, m of the graph.
iii) Given that K = 100D, determine the value of K.
PART B
You are provided with the following apparatus :
- a rectangular glass block
- four optical pins
- a piece of soft board
- a plain sheet of paper
- 4 thumb tacks
Proceed as follows
Place the plain sheet of paper on the soft board and fix it using the thumb tacks provided.
Place the glass block at the centre of the sheet, draw its outline. Remove the glass block.
(4 marks)
(2 marks)
(2 marks)
o
ii) Draw normal at point 2cm from the end of one of the longer side of the block outline. Draw a line at an angle of
from the normal. Stick two pins p1 and p2 vertically on this line.
By viewing through the glass from the opposite side stick two other pins P 3 and P4 vertically such that they are in line with
the images of the first two pins. Draw a line through the marks made by P3 and P4 to touch the outline. Extend the line P 1P2
through the outline (dotted line)
Measure and record the perpendicular distance d 1, between the extended line and the line P3P4
d1 = ................................................................ cm
(1 mark)
o
Repeat the procedure in above
d2 = ................................cm
(1 mark)
Hence find d = d1 + d2
2
(1 mark)
NB: The sheet of paper with the drawing MUST be handed in together with the question paper.
2. You are provided with the following apparatus :
- Two metre rule (not half metre rules)
- Two stands ad two clamps
- Two bosses
- One optical pin
- A piece of cellotape (and or plasticine)
- A spring
- One mass of 200g
- A stop watch
Proceed as follow
i) Set up apparatus as shown in the figure 1 below. Attach the pin (to act as the pointer) at one end of the metre rule using a
cellotape.
Page | 349
232/1,232/2,232/3 physics
ii) Suspend one end of the metre rule with a thread at 5cm mark from the end
iii) Suspend the other end with spring also 5cm from the end so that the metre rule is horizontal.
iv) Hold the other rule vertically on the bench so that it is near the end with a pointer as shown in the diagram above.
L0 ......................................................... cm
(1 mark)
a) Hang on the horizontal metre rule the 200g mass at a length l = 10cm from the spring record the extension, e, of the spring
in the table below.
b) Displace the mass slightly downward and release it to oscillate vertically. Take time for 20 oscillation and record in the
table below.
c) Repeat for other position of L, of the mass.
(4 marks)
vi) Plot a graph of extension, e (m) (y-axis) against T2(S)2 (5 marks)
vii) Calculate the gradient of the graph.
(2 marks)
viii) Given that determine the value of R.
(3 marks)
PART B
b) You are provided with a lens P a lens holder a white screen and a 30cm rule.
Procedure
i)Set the apparatus as shown in figure 4 below. Focus a sharp image of a distant object on the screen. The object should be
10cm away.The object should be at least 10cm away.
a) Measure the distance x in cm between the lens and the screen at which a sharp image is obtained repeat this two times,
Table 3
Object
Distance X, (cm)
1
2
ii) Calculate the average value of x.
iii) What is the physical significance of the result obtained in (iii) above?
(2 marks)
(2 marks)
(1 mark)
Page | 350
232/1,232/2,232/3 physics
BURETI SUB-COUNTY JOINT EVALUATION TEST
PHYSICS
Paper 1
July/August 2016
MARKING SCHEME
SECTION A :
1. 20.3cm3 - (0.1 x 50)cm2
20.3 - 5
= 15.3cm3
2.
K1 = F = 5 = 2.5Ncm-1
e 2
F = 2k1e
e= F = 5
= 1cm
2k1 2 x 2
3.
A1V1 = A2V2
πr2V1 = πR2V2
6 x 3 = 92V2
V2 = 6 x 6 x 3
9x9
= 1.333ms-1
4.
Unstable
When displaced slightly it occupies a new position
which is totally different from the original position
Clockwise moments = anticlockwise moments
1.2 x 0.5 = (U x 0.5) + (1.2 x 0.4)
0.6 = 0.5U + 0.48
0.5U = 0.6 - 0.48 = 0.12
U = 0.12 = 0.24
0.5
5.
U=V‫ ل‬g
0.24 = 13.5 x 10-6 x ‫ ل‬x 10
=
0.24
13.5 x 10-6 x 10
= 1777.78kgm-3
6.
7.
8.
Has no constriction Mercury thread contract and go
back to bulb before readings are taken
Readings of thermometer A is higher than that of
thermometer B
Black surfaces are better absorbers of radiant heat
Glass expand creating for space thus the fall. Water
expands at a higher rate than glass
9.
1.25
= 217.6m
11. Transformation of heat to and from other forms of
energy
SECTION B
12. a) Gas that perfectly obey gas laws at all conditions
b) i) When pressure is changed some time is allowed
for temperature to adjust to room temperature before
ii) k = slope = P = (3.0 - 0.6) x 105
1/V (3.6 - 0.7) x 106
= 2.4 x 105
2.8 x 106
= 8.571 x 10-2Nm
iii) Work done in compressing the gas
iv) The gas should be free from dust / particles
c) V1 = V2
T1 T2
13. i)
4000 = V2
310
340
V2 = 4000 + 340
310
= 4387.10l
Work done = mgh
= 30 x 10 x 10
= 3000J
ii) Work done by force = force x distance
= 100 x 10
sin 15o
= 3864J
iii)  = work done on load x 100%
work done by effort
= 3000 x 100%
3864
= 77.64%
iv) Work done to overcome friction
= 3864 - 3000
= 864J
v) M.A = L
E
= 300 = 3
100
14. i) CD - uniform deceleration
DE - the body is at rest
EF - uniform acceleration in the opposite direction
ii) a = V - 20 - 0 = 20 = 2m/s2
t 10 - 0 10
curve with 4o being lowest
labelling of axes
10. hHg ‫ ل‬Hgg = hair ‫ ل‬Hgg
750 - 748 x 13600 = hair x 1.25
1000
hair = 0.002 x 13600
iii) Average velocity = total displacement
time taken
½ (25 + 10)20 + (½ x 5 x -10)
40
= 350 - 25 = 325m = 8.125m/s
40
40
Page | 351
232/1,232/2,232/3 physics
b) i)
mv2 - mg = 0
r
0.25V2 - 0.25 x 10 = 0
1.6
0.15625V2 - 2.5 = 0
iii) Ft = m (v - u)
f = m (v - u)
t
= 30000 (15 - 20)
0.5
= -300,000N
d) This is due to the passengers reaction force on the
boat which acts backwards
16.
V = 4m/s
ii)
V = rw
4 = 1.6w
1.6
iii)
F = mv2 + mg
r
= 0.25 x 42 + 0.25 x 10
1.6
= 2.5 + 2.5= 5.0N
where
15. a) The ball has the same horizontal velocity as the
truck
b) Impulse is the change in momentum
c) i) M1V1 + M2V2 = (M1 + M2)V
30,000 x 20 + 0 = (30,000 + 10,000)V
V = 600000 = 15ms-1
40000
u - upthrust
mg - weight
T - tension
ii) T + mg = U
T + 10 x 10 = 3/4 x 0.04 x 1040 x 10
T = 312N - 100
T = 212N
c) i)Law of floatation - a floating object displaces its
own weight of fluid in which it floats
ii) Weighted bulb - to make the hydrometer float
upright and narrow to increase its
sensitivity
ii) S = Vt
= 15 x 15 = 225m
BURETI SUB-COUNTY JOINT EVALUATION TEST
PHYSICS
Paper 2
July/August 2016
MARKING SCHEME
SECTION A
1.
5.
2.
3.
4.
Using ampere’s swimming rule, the N-pole is deflected
to the right
- sound waves require a material medium to travel
while microwaves do not require a material medium to
travel / for transmission
- sound waves travel with slower speeds while
microwaves travel with the speed of light (3.0 x
108m/s)
- sound waves are longitudinal waves while
microwaves are transverse in nature
Initially the rod attracts electrons / negative charges
from the leaf to the cap, so the leaf falls. As the rod gets
closer to the cap, more electrons are attracted to the cap
so the leaf and the plate become positively charged
hence deflection
A - North pole
6.
B - South pole
1 1mk (tied)
30Ah → 1h = 30A
10min = 10 x 30
60
= 5A
n = real depth
apparent depth
1.33 =
2.4
apparent depth
apparent depth = 2.4 = 1.805cm
1.33
7.
Page | 352
232/1,232/2,232/3 physics
8.
Ip = 7.5A
correct wavefronts in A 1 > 1
correct wavefronts in C
3 = 1 > 2 and refracted away from the normal
Cp = 5 + 2.5
= 7.5µF
ii) P = I2R
= 7.52 x 2
= 112.5W
v = d = 1.4 x 106
c 7.5 x 10-6
v = 0.1867V
c) i) Power = 60 x 3 x 2 x 3hrs
1000
= 1.08kwhr
ii) cost = 1.08 x 6.30 x 7
= sh.47.628
d) To prevent electric shock
14. a) Capacitance increases
b) i)
9.
each ray incident and reflected
object position
10.
V - f f = v
l
= 3.0 x 108
7500/ 100
= 4.0 x 106Hz
11.
a + 8 = 234
b + 4 = 92
a = 226
b = 88
12. - replacing the screen with a photographic film
- placing a sliding card infront to act as a shutter
- painting inside black to avoid reflection
SECTION B
13. a) The magnitude of the induced e.m.f is directly
proportional to the rate of change of magnetic flux
b) i)
secondary power = 120 x 12
= 1440 watts
80% = 1440
100% = 100 x 1440
80
= 1800W
1800 = 240 x Ip
ii) Negative charges flow from the negative terminal
of the battery to one plate of the capacitor
Negative charges flow from the other plate of the
capacitor to the positive terminal of the cell
Hence equal positive and negative charges gather
on the plates opposing further flow of electrons
when fully charged or p.d across the plates is equal
to that of the battery
iii) To slow down the charging process so that current
and voltage are observed
c) i) The leaf falls
When U.V falls on the zinc plate electrons are
ejected / photoelectiric effect takes place
The negative charges in the zinc plate and cap of
the electroscope are repelled hence leaf falls
ii) There is no effect on the leaf of the electroscope
The electrons liberated by the UV light are
attracted back by the positive charges on the zinc
plate / cap of electroscope hence no effect on leaf
divergence
15. a) X-rays are produced when fast moving electrons hit
a metal target (or excited electrons lose energy in form
of X-rays)
Cathode rays are produced when a metal is heated
(by thermionic emission)
b) i) - cathode should be connected to then negative
terminal of a.c supply
- grid should be connected to the negative terminal
- the anode plates should be connected to the
positive terminal
- Y-plates should arranged to come before the Xplates
ii) By making the grid less negative w.v.t to the
cathode
iii) To conduct away electrons / cathode rays on hitting
the screen / reduce the accumulation of electrons on the
screen
iii) C.R.O - deflection system done by electrons held
while in the T.V tube deflection is done by the
Page | 353
232/1,232/2,232/3 physics
magnetic field
In a C.R.O there is a single time base while in a
T.V tube there are two time bases
c) i)
K.e = eV
= 1.6 x 10-19 x 100,000
= 1.6 x 10-14J
iii) 100% = 1.6 x 10-14
0.5% = 0.5 x 1.6 x 10-14
100
= 8.0 x 10-17J
8.0 x 10-17 = hc

= 2.486 x 10-9m
16. a) Temperature is kept constant physical conditions
are kept constant
Length of wire is constant
Thickness of wire is constant
b) i)
Rseries = 8 + 10
= 18
12 = I (18 + 2)
I= 12
20
= 0.6A
c) i) Convex / converging lens
If focuses images on a screen or forms a real image
ii) U + V = 100cm ½
hI = v = 2
h0 u
v = 2u
½
u + 2u = 1w
u = 100 = 33.33cm
3
v = 1w - 33.33
= 66.67cm
E = I (R + r)
R = 10 + 12 = 22
12 = I (22 + 2)
I = 12 = 0.5A
24
ii) RT = 24 x 12
24 + 12
= 8
d) p = 1
f
1=1+1
f u v
= 1
22.47 x 10-2
1 = 1 + 1
f
33.33 66.67
= 4.45D
f = 22.47cm
BURETI SUB-COUNTY JOINT EVALUATION TEST
PHYSICS
Paper 3
July/August 2016
MARKING SCHEME
1. a)
D1 = 0.32mm
½
D2 = 0.32mm
½
b) D = 0.32 + 0.32 ½
2
0.32 x 10-3m
½
c) x = 40cm
½
y = 60cm
½
d)
L (cm)
45
40
35
30
25
20
X (cm)
43.2
49
51.2
55
58.7
63.7
Y (cm)
56.8
51
48.8
45
41.3
36.3
Y
1.31
1.04
0.95
0.82
0.70
0.57
e) ii)
iii)
f)
2. a)
V
= 0.95 - 0.57
35 – 20
= 0.02533
K = 100 x 0.32 x 10-3
0.02533
= 1.263
outline
d1 = 2.1cm
d2 =3.6cm
d = 2.1 + 3.6
2
= 2.85cm
(V) Lo = 56cm (or any other value)
(b)
Page | 354
232/1,232/2,232/3 physics
Length L (cm)
Extension e (cm)
Time for 20 oscillation (sec)
Periodic time T (sec)
T² (sec)²
b)
10
20
30
40
50
8.8
0.088
12.22
0.611
0.37
7.7
0.077
11.21
0.561
0.31
6.6
0.066
1.12
0.506
0.26
5.6
0.056
9.15
0.458
0.21
4.5
0.045
8.20
0.410
0.17
labelled axes and unit
1mark
appropriate scale
1mark
plotting 4 or 5 correct by transferred
values
2marks
3 correctly transferred
1mark
best line
1mark
1mark
T2
Slope = (86 - 2.5) x 10-2
(3.6 - 0.5) x 10-1
= 6.1 x 10-2
3.1 x 10-1
= 0.1968m/s2
4π2
= 0.1968 x 4 x 3.142 x 3.142
= 7.771
ii) table
Object
1
2
Distance X, (cm)
10.1
9.9
iii) Average value of X
= 10.1 + 9.9 = 10.9cm + 0.1cm
2
iv) Physical significance of X = 10.0cm is the focal length of the lens used
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education
232/1
PHYSICS
Paper 1
July/August 2016
Time: 2 Hours
1. Figure 1 below shows a top view of two steel needles floating on water surface at a distance x metres apart.
Fig. 1
Very hot water is now poured at point P between the two needles. Explain any change in the distance x.
2. Figures 2a and 2b show a spring when carrying different masses.
(2 marks)
(2a)
(2b)
Determine :
i) the elastic constant of the spring.
ii) the length of the unloaded spring.
3. Figure 3 below shows an air balloon and a wooden block at equilibrium on a hot day.
(1 mark)
(2 marks)
Page | 355
232/1,232/2,232/3 physics
Fig. 3
Explain how the equilibrium would be affected when the weather suddenly becomes cold.
(3 marks)
4. Figure 4 below shows a cylindrical container having hot water at 95 oC. End A is shiny while end B is dull black. At equal
distances from the container is placed two identical gas jars fitted with thermometers X and Y. Compare the readings of the
two thermometers after two minutes.
(1 mark)
Fig. 4
5. Explain how the propellers on top of a helicopter help in lifting the helicopter above the ground.
(2 marks)
6. On the axes provided below, sketch a graph of displacement against time for a body moving with uniform deceleration.
(1 mark)
7. A car got a breakdown along a road inclined at an angle of 30 o to the horizontal. The driver used a stone to stop the car as he
looked for a mechanic. However, a boy removed the stone and the car still moved down the road without the driver. State
what provided the unbalanced force that made the car to accelerate downwards?
(1 mark)
8. Figure 5 below shows a screw jack whose pitch is 5mm. If the handle has a length of 40cm and the jack is 80% efficient.
Determine the effort needed to raise a car of mass 750kg.
(3 marks)
Fig. 5
9.
Some potassium permanganate crystals are introduced at the bottom of water in two cans. One can has hot water while the
other can has very cold water. Explain the container in which diffusion will diffuse faster.
(2 marks)
10. Figure 6 below shows a set up used by a form one student to measure the density of a solid that floats on water.
Fig. 6
Determine the density of the solid.
(3 marks)
11. State a factor that affects melting point of ice.
(1 mark)
12. A hot air balloon made from a very light material displaces 360kg of air and contain 300m3 of air of density 0.25kgm-3.
Determine the maximum load the balloon can lift.
(3 marks)
13. State the SI unit of momentum.
(1 mark)
SECTION B: (55 MARKS)
14. Figure 7(a) and 7(b) show the readings of a micrometer screw gauge before and after a drop of oil are placed at the jaws.
Fig. 7(a)(a)
Fig. 7(b)
When the drop was made to fall on a shallow tray having water whose surface was sprinkled with lycopodium powder, it
spread on the surface to form a patch of area Acm2. Given that the size of one molecule of oil is 3 x 10 -6cm.
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232/1,232/2,232/3 physics
a) Determine:
I. The diameter of the one drop of oil
(2 marks)
II.The area of the patch A
(3 marks)
b) State one assumption made in this experiment.
(1 mark)
15. State Archimedes' principle.
(1 mark)
b) Figure 8 below shows a spherical ball of radius 10.5cm in two immiscible liquids A and B of densities 1.2g/cm 3 and
0.8g/cm3 respectively. If 2/3 of the ball is inside A and 1/3 of the ball is in liquid B.
Fig. 8
Determine the weight of the ball.
(5 marks)
c) A gas is heated in a sealed container so that its volume cannot change. The graph below shows variation of pressure
against temperature of the gas.
Use the graph to determine
i) The pressure of the gas at 0oC.
(1 mark)
ii) The temperature at which the gas should exert zero pressure.
(2 marks)
iii) Give a reason why part (ii) above is not practically obtainable.
(1 mark)
16. a) Explain why it is easier to open the door when pushing further away from the hinge.
(1 mark)
b) Figure 9 below shows a simple form of a uniform diving board of weight 350N and length 2m.
A diver of mass 60kg walks from point Q towards end R and jumps into water when at a distance of 0.2m from end R.
Fig. 9
i) Determine the distance from point Q where the weight of the diving board acts.
(1 mark)
ii) In the axes provided below, sketch the graph of force exerted at P against distance of diver from R as diver moves from
Q towards R
(1 mark)
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232/1,232/2,232/3 physics
iii) Determine the force experienced at Q just before the diver jumps in water.
c) Figure 10 below shows a toy bird. State one method of increasing the stability of the bird on the support.
(4 marks)
(1 mark)
Fig. 10
17. a) Define the terms ‘frequency’ as used in uniform circular motion.
b) Figure 11 below shows a turn table, centre O with a mass of 30g at a distance of 6cm from the centre.
(1 mark)
Fig. 11
i) Determine the normal reaction between the 30g mass and the table.
(2 marks)
ii) The 30g mass just slides off the table when the turn table rotates at a frequency of 1 revolution per second. Determine:
I. The angular velocity.
(2 marks)
II. The coefficient of friction between the 30g mass and the table.
(3 marks)
iii) Oil is poured on the table and the table is made to rotate at the same frequency of 1 revolution per second. On the figure,
mark a point P along line OB where the 30g mass will just slide off.
(1 mark)
18. a) Distinguish between elastic and collision and inelastic collision.
(1 mark)
b) Figure 12 below shows two cars A and B moving in opposite direction along a straight road. The diagram shows their
respective positions at equal time intervals before the crush until the cars collided at point M. The diagram is drawn to scale
of 1:10
Fig. 12
i) Explain which driver had anticipated the collision.
(2 marks)
ii) If the time between all the intervals was 0.5 seconds.
I. Determine the velocities Vp, VQ and VR
(4 marks)
II. Car A had a mass of 8000kg while B had a mass of 1200kg. The cars coellesced and moved together a distance of 8m
before coming to rest.
Determine:
I. The velocity after collision.
(2 marks)
II.The common acceleration
(3 marks)
19. a) Figure 13 below shows two conductors A and B tightly fitted onto each other at the junction. When some ice was placed
at the junction then it became easy to separate the conductors. Explain which of the two a better conductor of heat was. (2
marks)
Fig. 13
b) Explain why a finger feels colder when dipped in methylated spirit than when dipped in water at the same temperature.
(2 marks)
c) 50g of ice at -5oC is dropped in a well lagged copper calorimeter of mass 30g having 150g of water at 80 oC. A final steady
temperature of 35oC is attained. Determine specific heat capacity of ice.
(Take specific heat capacity of water = 4200Jkg-1k-1, specific latent heat of fusion of ice =
340,00Jkg-1 and specific heat capacity of copper = 390Jkg-1k-1)
(4 marks)
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232/1,232/2,232/3 physics
d)
Figure 14 below shows a plastic bottle having a weighted cork floating on water inside the bottle.When the sides of the bottle
are squeezed the cork sinks.
Fig. 14
Explain the observation.
(2 marks)
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
Kenya Certificate of Secondary Education
232/2
PHYSICS
Paper 2
July/August 2016
Time: 2 Hours
SECTION A : (25 MARKS)
1. A vertical object placed on a bench is observed to have three shadows of different sharpness in different directions. Explain
this observation.
(3 marks)
2. The figure below shows two spherical materials, one an insulation conductor and the other a conductor. Negative charges are
introduced at point A in each case.
On the same figure indicate the final position of the charges. Explain your answer.
(2 marks)
3. Give a reason why attraction in magnetism is not regarded as a reliable method of testing for polarity.
4. A lady holds a large concave mirror of focal length 1m, 80cm from her face. State two characteristics of her image in the
mirror.
(2 marks)
5. The diagram below shows two parallel thick copper conductors connected to a d.c power supply. A rider made from thin
copper wire is placed on the conductors.
State and explain what is observed on the rider when the switch is closed.
(3 marks)
6. The audible frequency range for a certain person is 30Hz and 16500Hz. Determine the largest wavelength of sound in air the
person can detect. (Speed of sound in air = 330m/s)
(3 marks)
7. A small coin lies at the bottom of a water pond at a depth of 1.2m. How far from the water surface does the observer see it,
given the speed of light in water is 2.3 x 10 8m/s and velocity of light in air is 3.0 x 10 8m/s.
(4 marks)
8. State the cause of electromagnetic damping in a moving coil galvanometer.
(1 mark)
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232/1,232/2,232/3 physics
9. Diagram below is a resistor-capacitor circuit. At time t = 0, the switch is closed at A for some time and then opened. The
switch is then closed at B for some time.
On the axes provided below, sketch graph of voltage V across the capacitor against time t (t 1 and t2 represent time for opening
at A and closing at B respectively).
(3 marks)
10.
In the above diagram when the switch K is closed, the voltmeter shows a reading but when terminals of cell are reversed and
switch K closed the voltmeter reading is zero. Explain these observations.
SECTION B: (55 MARKS)
11. a) State the property of radiation that determines the number of electrons emitted when the radiation falls on a metal surface.
(1 mark)
b) The graph below is a variation of stopping potential, Vs, against frequency, f, in an experiment on photoelectric effect.
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232/1,232/2,232/3 physics
i) Explain what is meant by stopping potential. (1 mark)
ii) Given that the stopping potential Vs is related to the frequency by the equation
Vs = h f - W o
e
e
where e is the charge of an electron.
Determine the plank’s constant h. (e = 1.6 x 10 -19C)
iii) From the graph determine the work function wo for the metal in electron volts (eV)
12. a) Diagram below represents a metre bridge used to determine the resistance of an electrical component, X.
(4 marks)
(3 marks)
From the diagram,
i) Explain why wide brass strips are used as terminals.
(1 mark)
ii) Explain why a cell of low e.m.f is preferable.
(1 mark)
iii) If null deflection was obtained when l1 was 60.0cm. Calculate the resistance of component marked X.
(2 marks)
iv) State three ways of ensuring that the error is minimized.
(3 marks)
b) A uniform resistance wire of length 2.0m conducts a current of 0.25A when connected in series with a cell of e.m.f of
1.6V. How much current would be conducted if the wire is now cut into 2 equal lengths which are then arranged in parallel.
(4 marks)
13. a) State two factors that affect the strength of an electromagnet.
(2 marks)
b) Figure below shows suspended metre rule in equilibrium balanced by the magnet and weight shown. The iron core is
fixed to the bench.
i) State and explain the effect on the metre rule when the switch S is closed.
ii) State and explain the effect on the metre rule when the terminals of battery are reversed.
iii) Suggest how J on the set up can be varied to have metre rule tilt anticlockwise faster.
iv) Explain your suggestion in b(iii) above.
14. a) The diagram below is a section of a house wiring system.
(3 marks)
(2 marks)
(1 mark)
(3 marks)
Page | 361
232/1,232/2,232/3 physics
Name:
i) Circuit labelled P
(1 mark)
ii) Terminals labelled X and Y
(2marks)
iii) State the purpose of R in the circuit, hence explain why R is connected to Y and not X.
(2 marks)
iv) Why is the earthing necessary in such a circuit?
(1 mark)
b) The cost of electricity per kilowatt hour- kWh is Ksh.8, determines how much a household running a device rated 1500W
continuously for 1.08 x 105 seconds, would pay.
(2 marks)
c) Explain reason for transmission of electrical power over along distance at very high voltage.
(1 mark)
d) Explain why for transmission of electrical power over long distance, alternating current (a.c) is preferred to a direct
current (d.c)
(1 mark)
e) How many 1000W electric iron rating could be safely connected to a 240V main circuit fitted with 13A fuse?(3 marks)
15. a) State Lenz’s law of electromagnetic induction.
(1 mark)
b) The figure below is a simple microphone in which sound waves from a speaker cause the cardboard diaphram to vibrate.
i) Explain how a varying current is induced in the coil when the diaphram vibrate to and fro.
(3 marks)
ii) State two ways in which the induced current in 15b(i) above can be increased.
(2 marks)
c) A transformer with 1200 turns in the primary circuit and 120 turns in the secondary circuit has its primary circuit
connected to a 400V a.c. source. It is found that when a heater is connected to the secondary circuit, it produces heat at the
rate of 600W. Assuming 100% efficiency, determine the:
i) voltage in the secondary circuit.
(2 marks)
ii) current in the primary circuit.
(2 marks)
iii) current in the secondary circuit.
(1 mark)
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
232/3
PHYSICS
Paper 3
July/August 2016
Time: 2½ Hours
1. You are provided with the following apparatus :
- two retort stands
- two clamps
- two bosses
- one 50g mass
- one stop watch
- two metre rules
Proceed as follows:
a) i) Set up the apparatus as shown in figure 1 below.
Fig. 1
Page | 362
232/1,232/2,232/3 physics
Attach the ends of the thread to the metre rule and fasten the loops tightly so that the distance between the loops,
d = 80cm. (Note : L1 = L2 = 50cm and should remain the same throughout the experiment)
iii) Tie the 50g mass with a thread 20cm long. Fasten the mass at the centre of the thread on the rule such that the length of
the pendulum from the point of suspension is 10cm as shown above.
b) i) Measure the angle 2
ii) Pull the mass towards you through a small angular displacement and release it to swing freely.
The mass should oscillate perpendicular to the plane of the metre rule. Time 10 oscillations..
iii) Repeat procedure b(i) and (ii) above by using different values of d and enter your values in table 1 below.
Table 1
d (m)
0.8
0.7
0.6
0.5
0.4
0.3
2

cos 
Time for 10 oscillations, t (s)
Periodic time T(s)
T² (S²)
(10 marks)
c) On the grid provided below, plot a graph of T 2 (y-axis) against cos .
(5 marks)
d) Find the slope, S, of the graph.
(3 marks)
e) Given that S = 1.6π2, determine the value of K.
(2 marks)
K
2. You are provided with the following:
- a 100ml beaker
- a 600ml beaker
- 2 thermometers range -10oC to 110oC
- a 100ml measuring cylinder (can be shared)
- some plasticine
- vernier callipers ( can be shared)
- metre rule or half metre rule
- some boiling water
- 100ml methylated spirit (at room temperature) in a beaker
- stop watch
- a stirrer
Proceed as follows:
a) Using the vernier callipers, measure the internal diameter d 1 and external diameter d2 of the 100ml beaker.
d1 = ...... cm
d2 = ...... cm
(1 mark)
Hence determine the thickness, X, of the glass wall of the beaker given that
X = d2 - d1
2
X = .....cm
(1 mark)
b) Using the measuring cylinder provided, pour 80ml of methylated spirit into the small beaker. Measure the height, h, of the
methylated spirit in the small beaker.
h = ..... cm
(1 mark)
Hence determine the area, A, of the glass walls in contact with water, given that
A = πd1h
A = ...cm2
(1 mark)
c) Using the plasticine provided, make a circular disc of about the same area as the bottom surface of the smaller beaker and
about 1cm thick. Place this disc at the bottom of the larger beaker and place the small beaker on it. (The plasticine may be
placed in a thin transparent polythene paper)
Now pour boiling water into the larger beaker until the levels of water in the two beakers are the same. See figure 2 below.
Figure 2
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232/1,232/2,232/3 physics
d) Place a thermometer in the hot water and stir gently until the temperature drops to 80 oC. Now start the stop watch and
measure the temperature, T1, of the hot water at intervals of 20 seconds. Record the values in the table 2. (Stir the water in
the two beakers before taking readings)
Pour out the contents of the two beakers.
e) Measure another 80ml of methylated spirit and put into the small beaker. Place the small beaker inside the larger beaker on
the plasticine disc as before.
Again pour boiling water into the larger beaker until the levels of the water and the methylated spirit in the two beakers are
the same. Place one thermometer in the methylated spirit and another in hot water. Stir gently until the temperature of the hot
water drops to 75oC. Start the stop watch and immediately read and record in table 2 the temperature T 2, of methylated spirit.
(You may now remove the thermometer in the hot water)
Read other values of T2 at intervals of 20s and record in table 2
Table
Time, t (seconds)
Temperature T1 (°C)
Temperature T2 (°C)
0
20
40
60
80
100
120
140
160
180
200
f) Plot a graph of temperature, T 2, (y-axis) against time, t.
(5 marks)
g) i) Determine the slope, S, of the graph at time t = 90 seconds.
(3 marks)
ii) Determine the constant K, given that K = 315 SX
A (T1 - T2)
where T1 and T2 are the temperatures of the hot water and methylated spirit at t = 90s and X and A are in m and m2
respectively.
(2 marks)
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
PHYSICS
Paper 3
July/August 2016
CONFIDENTIAL INSTRUCTIONS
The information contained in this paper is to enable the head of the school and the teacher incharge of Physics to make
adequate preparations for this year’s Physics Practical examination.
NO ONE ELSE should have access to this paper or acquire knowledge of its contents. GREAT CARE must be taken to
ensure that the information herein does not reach the candidates either directly or indirectly. Doing so will constitute an
examination irregularity which is punishable.
Each candidate will require the following apparatus :
Question 1
- 2 metre rules
- two retort stands
- two clamps
- one 50g mass
- one stopwatch
- two bosses
Question 2
- 100ml of beaker (glass)
- 600ml glass beaker
- 2 thermometers range -10oC to 110oC
- a 100ml measuring cylinder (can be shared)
- some plasticine
- vernier callipers (can be shared)
- metre rule or half metre rule
- some boiling water
- 100ml methylated spirit (at room temperature) in a beaker
- stop watch
- a glass stirrer
Page | 364
232/1,232/2,232/3 physics
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
PHYSICS
Paper 1
July/August 2016
MARKING SCHEME
1.
x becomes larger
Hot water breaks surface tension
(of water making water to pull apart)
2. i) extension = 0.25 - 0.20 = 0.05m
force = 0.5 - 0.2 = 0.3N
K = F = 0.3 = 6Nm-1
e 0.05
ii)
Net original length be 10 extension
0.2 - lo
0.2 = 6(0.2 - lo)
0.2 = 0.2 - lo
6
lo = 0.2 - 0.2
6
= 0.1667m
(Look for alternative working)
3. The system will tip to the left
Balloon (air) contracts more than solid hence lower
upthrust on balloon than on solid
4. X lower than Y (Y higher than X)
Dull black surface emits more radiant heat than shiny
surface
5. As propellers rotate at high speed pressure above
helicopter is lowered
Higher pressure below the helicopter pushes it upwards
6.
7.
8.
9.
Net force was provided for by the action of mg sin 30
i.e. action of force along incline
VR = 2 x 3.142 x 0.5 = 3.142cm
Efficiency = MA x 100 %
VR
80 = MA x 100
3.142
MA = 80 x 3.142 = 2.513
100
But MA = L = E = L
E
MA
= 7500
2.513
Effort = 2984.16N
E = MA x 100% and MA = L
VR
E
Accuracy
Diffusion faster in can having hot water
Increase in temperature increases rate of diffusion
=M
 V
= 30g
= 30g
37.5 - 35
2.5
= 12gcm-3
11. Impurity
Pressure
12. upthrust = wt of air displaced
= 3600N
But V = V  g
wt for air = 300 x 0.25 x 10= 750N
= upthrust - weight
= 3600 - 750
= 2850N
13. Kilogram metre per second
14. a) I. Diameter at one drop
= 2.32 - 0.26
= 2.06mm
II. Volume of drop = 4/3 x 3.142 x (0.206)3
= 0.03662cm3
But t = V  A = V
A
t
= 0.03662
3 x 10-4
= 0.03662 x 109
3
0.01221 x 104
= 1.221 x 102cm
b) Oil spreads to monolayer thickness
Oil drop is assumed to be perfectly spherical
15. a) When a body is wholly or partially immersed in a
fluid, it experience an upthrust equal to weight of fluid
displaced
b) Volume of liquid A displaced
2
/3 x 4/3 x 3.142 x (10.5)3 = 3233.12cm3
10.
Wt of liquid A displaced
= 3233.12 x 10-6 x 1200 x 10
38.8N
Volume of liquid B displaced
= 1/3 x 4/3 x 3.142 x (10.5)3
= 1607.3cm3
Wt of liquid B displaced
= 1607.3 x 10-6 x 800 x 10
= 12.86N
Total upthrust
= 38.8 + 12.86 = 51.66N
Weight of sphere = 51.66N
c) i) 100KPa
ii) -275K
iii) Real gases liquefy before reaching absolute
zero temperature
16. a) The longer the distance from the fulcrum, the lower
the force (required to maintain equilibrium)
b) i) 0.2m
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232/1,232/2,232/3 physics
ii)
the two definitions must be connected with words
like ‘while’ ‘whereby’ etc.
b) i) B anticipated collision since he decelerated
ii) Vp = 1cm = 2cm = 2cms-1
0.5
VQ = 0.5 = 1cm s-1
0.5
VR = 2cm = 4cms-1
0.5
Accept line or curve with negative slope
Distance intercept must exist
F1d1 = F2d2
iii) 0.6 x 600 = 350 x 0.2 + Fp x 1.2
360 = 70 + 1.2Fp
290 = 1.2Fp
Fp = 290 = 241.67N
1.2
Force at Q = 600 + 350 + 24.67
1191.67N
c) - making feet shorter
any one correct
17. a) Number of complete oscillations made per second
( or cycles per second)
b) i)
R = W = mg = 30 x 10 = 0.3N
1000
ii) I.
w = 2πf
= 2 x 22/7 x 1 = 6.284rad s-1
II.
FR = mw2r
= 0.03 x (6.284)2 x 0.06
= 0.007107N
But u = FR = 0.007107
R
0.3
= 0.2369
P on line OB but nearer O
18. a) Elastic collision is where both momentum and
kinetic energy are conserved while inelastic collision is
where only
momentum is conserved but not
kinetic energy
iii) Total momentum before collision
= m1v1 + m2v2
= 8000 x 0.02 + 1200 x -0.01
= 16 - 12
= 4kgms-1
let final velocity be V
m1v1 + m2v2 = (m1 + m2
H = (8000 + 1200
4 = 9200V
V= 4
9200
= 0.0004348ms-1
b) v2 - u2 = 2as
O2 - u2 = 2 x a x 8
- (4 x 348 x 104)2 = 16a
a = -16 x 10-8 = -1 x 10-8ms-2
16
19. a) B was better conductor since it contracted more
than A (for easy separation)
b) Spirit (being more volatile) picks more latent heat
of vaporization from the finger causing more cooling
than water
c) Heat gained by ice = heat lost by water + heat lost
by calorimeter
0.05C (5) + 0.05 x 340000 + 0.05 x 4200
x 12
= 0.03 x 390 x 68 + 0.15 x 4200 x 68
0.25C + 17000 + 2520 = 795.6 + 42840
0.25C + 19520 = 43635.6
0.25C = 43635.6 - 19520
0.256 = 24115.6
C = 24115.6
0.25
= 96462.4Jkg-1k-1
d) Squeezing increases the pressure of air above the
water
Pressure below water becomes lower and the cork
moves down
Page | 366
232/1,232/2,232/3 physics
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
PHYSICS
Paper 2
July/August 2016
MARKING SCHEME
1. Three different sources of light
Three sources of light of different intensities
Three sources at different distances from the object
2.
3.
4.
5.
6.
7.
NB:
Charges at insulator inside while conductor outside
The conductor allows charge to be distributed while an
insulator does not
Attraction occurs between unlike poles of a magnet and
can also occur between a magnet and unmagnetised
magnetic material
Magnified
Upright / erect
Virtual
any two
The rider moves towards the magnet away from power
supply The conductor experiences a force when placed
in magnetic field due to interaction between two
magnetic fields
V = fl
 = 330
30
= 11m
Apparent depth =
real depth
refractive index
Refractive index n = velocity in air
velocity in water
= 3.0 x 108
2.3 x 108
= 1.3
Apparent depth = 1.2
1.3
= 0.92m
8. Eddy currents
electrons
3-0
e (12 - 4.4) x 1014Hz
~ 3.95 x 10-15
h = 3.95 x 10-5 x 1.6 x 10-19
= 6.32 x 10-34js
iii) y intercept = wo
e
- wo = -16V
e
wo = 1.6eV
Evidence read from graph + 1 small sq.
(1.55 - 1.65)
12. a) To minimise resistance due to
i) Terminals
ii) To minimise current and the resulting heating
effect that would alter resistance
iii) x = 60 or l1 = RX
20 40
l2 R
x = 60 x 20
40
= 30
iv) Use of short connecting wires
Use of a source with low e.m.f
The value of known resistance R should be
comparable to X
b) R = V
A
= 1.6
0.25
= 6.4
Resistance of each piece = 6.4
2
= 3.2
RT = R1R2 (parallel)
R1 + R2
= 3.2 x 3.2
3.2 + 3.2
= 1.6W
I = 1.6  V
1.6
R
= 1A
9.
10. Voltmeter show reading when switch is closed and
diode is forward biased. Reversing terminals reverses,
biasing and no current flows
The depletion layer widens and potential hill increases
SECTION B
11. a) The intensity of radiation
b) i) Stopping potential is the opposing / negative
potential sufficient to just stop the movement of
13. a) Amount of current
Number of coils / turns
Shape of the core
b) i) The metre rule tilt anticlockwise when switch is
closed current flows in coil magnetising bar. End of
coil facing magnet become south pole hence attract
magnet to which ruler is attached
ii) Metre rule tilt clockwise or weight comes down
while magnet moves upwards. Reversing terminals
reverses direction of current hence polarity of electro
magnet. End facing magnet become North Pole hence
repulsion
iii) Move jockey J from B toward A / right to left of R.
Page | 367
232/1,232/2,232/3 physics
It reduces resistance and increase current hence
stronger
electromagnet
14. a) i) P - main ring circuit
ii) X - neutral terminal
Y - positive / live terminal
iii) To protect / guard against excess current
Ensure when R breaks the appliance does not
remain live
iv) To guard against electric shock channel / transfer
excess charges to ground
b) kwh
h
sh.
15000 x 1.08 x 105 x 8
1000
3600
= 360
b) i) As the diaphram vibrate due to sound wave
impact to and fro, it causes the coil to move forth and
back in magnetic
field cutting field lines
This causes a varying electro-magnetic force to be
induced in the coil which causes a varying current to
flow
ii) Increase impulsive force of sound waves to
diaphram
Increase sound frequency
Increase no. of turns
Increase strength of magnet / use magnet with
closer poles
any two
c) i)
Vp = N p = I s
Vs N s I p
Vs = 400 x 120
1200
= 40V
c) High voltage leads to low current hence lower
power losses
d) Alternating current (a.c) can easily be stepped up to
high voltage
e) IV = No. of irons x 1000
Number = 13 x 240
1000
= 3.12
Accept 3 only
15. a) The induced current flow in such a direction that
produces magnetic effect that oppose the change
producing it
1.
ii) Ip = V = 600
R 400
= 1.5A
iii) Is = P = 600
V 40
= 15A
GEM SUB-COUNTY FORM 4 JOINT EVALUATION
PHYSICS
Paper 3
July/August 2016
MARKING SCHEME
b (iii)
d (m)
2
0.8

cos 
Time for 10 oscillations
Periodic time T(s)
T² (S²)
112
0.7
86
0.6
72
0.5
60
0.4
46
0.3
35
56
0.5592
13.25
1.325
1.7556
43
0.7314
14.09
1.409
1.9852
36
0.8090
14.22
1.422
2.0221
30
0.8660
14.87
1.487
2.2112
23
0.9205
15.32
1.532
2.3470
17.5
0.9537
15.59
1.559
2.4305
c) On Graph
d) Slope, S = change in T2
change in cos 
= 2.15 - 1.2
0.88 -0.5
= 2.7143S2
2.
e) K = 1.6π2
S
= 1.6 (3.142)2
2.7143
= 5.8194S-2
a) d1 = 3.50cm + 0.1
d2 = 5.21cm + 0.1
X = 0.855cm
b. h = 4.0cm + 0.1
A = 43.988
Time t (seconds)
Temperature T1 (°C)
Temperature T2 (°C)
0
80.0
21.0
20
76.0
25.0
40
73.0
29.0
60
70.0
33.0
80
68.0
37.5
100
66.0
43.0
120
64.0
47.0
140
62.0
52.5
160
60.5
58.0
180
59.0
64.0
200
57.5
68.0
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232/1,232/2,232/3 physics
f) A graph of T2 (y-axis) against time.
g) i) Slope S at t = 90S
48.5 - 24.0 = 24.5 = 0.2722
130 - 20
90
ii) K = 315 SX = 315 x 0.2722 x 0.855
A(T1 - T2) 43.988 (64.0 - 40.0)
= 74.63025
1,055.712
= 0.0707 (4d.p)
1.
2.
MAARA FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/1
July/August 2016
Time: 2 hours
SECTION A (25 marks)
Answer ALL the questions in the spaces provided.
The water level in a burette is 30.6cm³, 50 drops of water each of volume 0.2cm³ are added to the water in the burette. What
is the final reading of the burette.
(2 marks)
Figure 1 shows a graph showing the behaviour of a helical spring.
Fig 1
Determine the spring constant in SI units.
(3 marks)
3. Two forces are acting on a body as shown in figure 2.
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232/1,232/2,232/3 physics
Fig 2
By use of a vector, draw the body and show the resultant force.
(1 mark)
4. Two identical beakers A and B containing equal volumes of water are placed on a bench. The water in A is cold while in B is
warm. Identical pieces of potassium permanganate are placed gently at the bottom of each beaker inside the water. It is
observed that the spread of colour in B is faster than in A. Explain this observation.
(2 marks)
5. Figure 3 shows a uniform bar of weight 5N and length 1.1m pivoted at a point and in equilibrium under the action of the forces
shown.
Fig 3
Determine the value of weight W.
6. State the contribution physics has made to the entertainment industry.
7. State one limitation of the micrometer screw gauge.
(3 marks)
(1 mark)
(1 mark)
8.
Fig 4
State the law represented in figure 4.
9. Alcohol was placed in a flask fitted with an air tight cork as shown in figure 5.
(1 mark)
Fig 5
State and explain what would be observed if the flask was cooled.
(3 marks)
10. A boy poured some boiling water into a plastic can and placed an air-tight cork on its open end. He then ran some cold water
on it for about 20 seconds after which he shook the can vigorously. State and explain what he observed.
(3 marks)
11. Water flows along a horizontal pipe of cross-sectional area 30cm². The speed of the water is 4m/s but it reaches 7.5m/s in a
constriction in the pipe. Calculate the area of the constriction in m²
(3 marks)
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12. The arrangement in figure 6 was used to determine the specific heat capacity of the metal.
Fig 6
State the precautions that need to be taken.
13. State Newton's second law of motion.
SECTION B : (55 marks)
Answer ALL questions in this section.
14. a) i)State two conditions necessary for equilibrium of a body acted upon by a number of forces.
ii) Figure 7 shows beaker containing a block of ice.
(2 marks)
(1 mark)
Fig 7
State and explain the change in stability when the ice melts.
b) Figure 8 shows a drop of fatty acid on a wire of diameter 1.4mm
Fig 8
When the drop of the fatty acid was placed on clean water surface it formed a circular patch of diameter 91cm.
i) Estimate the length of the molecule of the fatty acid.
ii) State the assumption made in part (i) above.
15. a) State the principle of transmission of pressure in liquids.
b)A mass of 80kg is being lifted by a force F applied on the other piston of the machine as shown in figure 9.
(3 marks)
(3 marks)
(1 mark)
(1 mark)
Fig 9
Determine the value of F needed to just lift the 80kg mass given the density of the liquid is 1.2g/cm³.
(4 marks)
c) Give one reason why a lift pump raises water to heights less than 10m.
(1 mark)
d) In an experiment, it was observed that soapy water placed on a wet smooth surface displaced the particles of non-soapy
water. Sate and explain this observation.
(2 marks)
16. a)A block of metal of mass 250g at 100°C is dropped into a lagged calorimeter of heat capacity 40JK -1 containing 100g of
water at 25°C. The temperature of the resulting mixture was found to be 40°C. Determine; (Cw = 4200Jk-1)
i) Heat gained by calorimeter.
(2 marks)
ii) Heat gained by water.
(2 marks)
iii) Heat lost by the block.
(2 marks)
iv) Specific heat capacity of the metal block.
(3 marks)
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232/1,232/2,232/3 physics
b) Hot milk in a bottle cools faster when wrapped in a wet cloth than when the bottle is immersed in cold water in a bucket.
Explain.
(2 marks)
17. a) The machine represented in the diagram can be used to lift water from a well.
Fig 10
A force of 50N applied on the handle lifts water of weight 180N
i) Calculate the efficiency of the machine.
(4 marks)
ii) Give a reason why the efficiency is less than 100%.
(1 mark)
b)The five-tick tape shown below was produced by a ticker timer connected to mains supply of 50Hz when a force pulls the
trolley.
Fig 11
Determine the acceleration of the trolley.
(4 marks)
18. a)i) State Archimede's principle.
(1 mark)
ii)Figure 12 shows a buoy, M, of volume 120 litres and mass 60kg. It is held in position in sea water of density 1.04g/cm³
by a light cable fixed to the bottom so that ¾ of the volume of the buoy is below the surface of the sea water.
Fig 12
Determine the tension T in the cable.
(4 marks)
b)i) During cold season boys looking after cattle lit a fire in a Kimbo tin and whirl it round vertically without its contents
falling out. Explain.
(1 mark)
ii)A particle is moving in a circular path of radius 0.4m with velocity of 7.5m/s. Determine its angular velocity. (3 marks)
19. a) State a condition which should be attained by a body in a viscous fluid to have terminal velocity.
(1 mark)
ii)A block of metal having a mass of 30kg requires a horizontal force of 100N to move it with uniform velocity along a
horizontal surface. Calculate the co-efficient of friction.
(3 marks
b)i) State Charles' law.
(1 mark)
ii) Give three reasons why gas laws do not hold at low temperatures.
(3 marks)
c) Distinguish between elastic and inelastic collisions.
(1 mark)
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232/1,232/2,232/3 physics
MAARA FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/2
July/August 2016
Time: 2 hours
SECTION A (25 marks)
1. Figure 1 show a method used to charge conductors. The procedure follows steps a, b and c
Fig 1
2.
3.
4.
5.
6.
i) State the method of charging above.
(1 mark)
ii) Explain what happens in step (b) above.
(1 mark)
In the space provided below, sketch a labelled diagram to show how a pinhole camera forms an image of a vertical object
placed infront of the pinhole.
(3 marks)
Define resistance of a Ohmic conductor.
(1 mark)
State one reason why convex mirrors are used as driving mirrors.
(1 mark)
How much current is taken by a bulb rated 100w, 250V.
(2 marks)
Figure 2 shows an experimental arrangement S1 , S2 and S are narrow slits.
Fig 2
State what is observed on the screen when the source is white light.
7. An x-ray machine produces radiation of wavelength 1.5 × 10 -11m. Calculate the energy content.
(Planks constant (h) = 6.63× 10-34+)
8. A student set up an experiment in the laboratory as shown in figure 3.
(1 mark)
(2 marks)
Fig 3
He directed a U.V light on the cathode of the photocell and observed that the galvanometer deflects.
i) Explain this observation.
(1 mark
ii) State one condition that must be met for the galvanometer to deflect.
(1 mark)
9. Figure 4a and figure 4b shows a P-N junction connected to a battery. It is observed that the current in figure 4a is greater than
the current in figure 4b
Fig 4a
Explain the observation.
Fig 4b
(2 marks)
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10. Figure 5 shows a relationship between potential difference V and the charge Q across and stored in a capacitor.
Fig 5
Determine the capacitance C of the capacitor.
(3 marks)
11. Very strong x-rays have the same properties as gamma rays. What is the main difference between these two electromagnetic
waves.
(1 mark)
12. Figure 6 shows a radioactive substance contained in a thick lead box and emitting radiations B, C and D. Passing through a
strong field directed out of the plane of the paper.
Fig 6
Identify with a reason the radiation labelled D.
(2 marks)
13. An object of height 10cm stands before a diverging lens of focal length 30cm and at a distance of 20cm from the lens.
Determine the image distance.
(3 marks)
SECTION B (55 marks)
Answer ALL question in this section
14. a)
Fig 7
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232/1,232/2,232/3 physics
i) Use figure 7 above to answer the question that follow; target T is made of a material of high melting point. Give a reason for
this.
(1 mark)
ii) State two reasons why oil is used for cooling instead of water.
(2 marks)
iii) What property does the material marked R have that makes it suitable for shielding.
(1 mark)
iv) How can the intensity of x-rays produced be increased.
(1 mark)
b) Figure 8 below shows the main components of a cathode ray oscilloscope.
Fig 8
Name the parts labelled A and B.
(2 marks)
ii) What is the function of parts labelled C.
(1 mark)
iii) Explain how elections are produced.
(1 mark)
iv) Give a reason why the tube is evacuated.
(1 mark)
15. a)i)In a consumer fuse box in domestic wiring, use of circuit breakers is preferred to fuses. State two advantages of using a
circuit breaker over a fuse.
(2 marks)
ii)A house is supplied with 240V from a power source which is fitted with a 13A fuse. What is the maximum number of 75w
bulbs that can be fitted in the house.
(2 marks)
b) Figure 9 shows two circuits close to each other.
Fig 9
When the switch is closed, the galvanometer shows a reading and then returns to zero. When the switch is then opened, the
galvanometer shows a reading in the opposite direction and then returns to zero. Explain this observation.
(3 marks)
b) Explain how energy losses in a transformer are reduced by having a soft-iron core.
(2 marks)
16. a) i) What is a virtual image?
(1 mark)
ii) Complete the ray diagram in figure 10 below so as to form an image.
(3 marks)
Fig 10
II. State two characteristics of the image formed.
b)i) A ray of light is incident on a glass-water interface as shown in figure 11 below.
(2 marks)
Fig 11
Calculate the angle of incidence i. (Take the refractive index of glass and water 3/2 and 4/3 respectively.
ii) State one application of total internal reflection.
iii) Prisms are preferred to plane mirrors for use in periscopes. Explain.
17. a) State two advantages of the alkaline accumulator over lead acid accumulator.
b) Figure 12 shows resistors in a circuit.
(3 marks)
(1 mark)
(2 marks)
(2 marks)
Fig 12
Page | 375
232/1,232/2,232/3 physics
Calculate
i) The total resistance of the circuit.
ii) Current through the 6resistor.
18. a)i) The diagram below (figure 13) shows a mass oscillating on a spring above point m.
(2 marks)
(3 marks)
Fig 13
Identify the point at which
I. The system has maximum KE
II. The kinetic energy is equal to potential energy.
ii) Distinguish between electromagnetic waves and mechanical waves giving an example in each.
b) Figure 14 shows a standing wave on a string of length 27cm.
(1 mark)
(1 mark)
(2 marks)
Fig 14
Determine the wavelength of the wave.
c) Other than temperature state two other factors that affect speed of sound in air.
19. a)
(3 marks)
(2 marks)
Fig 15
In figure 15 above an insulated copper wire XY lies over the fixed wire AB connected to a battery. When the key in the
circuit is closed, the rod XY moves.
i) In which direction does the wire XY experience the force? Indicate using an arrow.
(1 mark)
ii) When is the force on the wire XY greatest.
(1 mark)
iii) What is the effect of reversing both the magnetic field and direction of flow of current.
(1 mark)
iv) How can the speed of the rod be decreased.
(1 mark)
c) i) Attraction is not the sure way for testing polarity of a magnetic. Explain.
(1 mark)
ii)Figure 16 below shows two similar iron pins. One is placed on a wooden block and the other on a soft iron block.
Fig 16
It was observed that the pins on the wooden block were attracted to the magnet while the other on the soft iron block was
not. Explain.
(2 marks)
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232/1,232/2,232/3 physics
MAARA FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/3
July/August 2016
Time: 2½ hours
1.
Part A
You are provided with the following.
- Two metre rules.
- A stop watch.
- A half-metre rule
- Two retort stands.
- A pendulum bob.
Proceed as follows:
a) Clamp one of the metre rules horizontally so that its largest face is in plane and then suspend the second metre rule on the clamped metre rule
so that it balances horizontally as shown in figure 1
b) Set the length of the thread suspending the metre rule, attached to it at A to 30 cm.
Fig 1
Tie a second thread attached at B to support the suspended metre rule at a distance D = 25cm from A
c) Suspend the pendulum bob with a thread at l =25cm from B so that its length is 20cm as shown in figure 1
d) Displace the hanging metre rule in a horizontal plane as shown by the arrowed lines in figure 1 to set it into horizontal oscillations.
Measure the duration, t of ten complete oscillations and a record in table 1 against the value 25cm of D. Calculate the record the period, T
and its square T²
e) Repeat for the other values of D shown in table 1.
(7 marks)
Table 1
D(cm)
t (seconds)
T (seconds)
T² (Second²)
25
30
35
40
45
f) Plot the graph of D (cm) against T²(Second²)
g) Determine the slope, S of the graph.
PART B
You are provided with the following,
- A round-bottomed flask containing some water and fitted with a delivery tube.
- A thermometer.
- A balance
- A measuring cylinder.
- A thermometer
- A retort stand
- A calorimeter
- A Bunsen burner.
Proceed as follows
h) Clamp the flask and heat the water as shown in figure 2 and heat the water.
(5 marks)
(2 marks)
Fig 2
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232/1,232/2,232/3 physics
i) Measure the mass, mC the calorimeter can and stirrer.
mc = kg.
(1 mark)
j) Measure 60cm³ of water and put it in the calorimeter can.
k) Measure the mass of the calorimeter can, stirrer and the water, m1
m1 = kg.
(½ mark)
l) Measure the temperature, T1 of the water in the calorimeter can.
T1 =°C
(½ mark)
m) Place the can and its contents into the Jacket. When the steam is issuing freely from the delivery tube, dip the end of the delivery tube into
the water in the calorimeter can and keep stirring until the temperature of water rises by 25°C
Note the new temperature T2 as you quickly remove the tube form the water.
(1 mark)
n) Measure the mass m2 of the calorimeter and its content and hence determine the value of m = m2 - m1
m2 = kg
(1 mark)
o) Calculate the quantity n given than
mn = 100
(Where mw in the mass of water that was put in the calorimeter can, t is temperature change of the can and its contents, r is the change of the
temperature of the condensed steam.)
(2 marks)
2. PART A
You are provided with the following:
- A switch
- A resistance wire mounted on a millimeter scale
- Six connecting wires.
- An ammeter
- A voltmeter
- A micrometer screw gauge
- A pair of cells.
Proceed as follows.
a) Measure the diameter, d of the resistance wire.
i) d = mm
(½ mark)
ii) d = m
(½ mark)
b) Connect the circuit as shown in figure 3
Figure 3
i) Close the switch S and measure the potential difference , V o cross the 1.0m length of resistance wire and current, Io
VO =
(1 mark)
Io =
(1 mark)
ii) Calculate the resistance, Ro of the wire PQ
(1 mark)
iii) Calculate the area of the cross-section, A of the wire.
(1 mark)
iv) Determine the constant, K of the wire from the relation Kl = RoA, where l is the length of the wire and A is the area of the cross-section of
the wire.
(2 marks)
PART B
You are provided with the following
- A soft board
- Four optical pins
- Two thumb pins
- One half-metre rule
- One glass prism
- 2 Sheets of white paper.
- Some plastacine
Proceed as follows:
c) Measure one of the angles of the prism (the refracting angle), A
(1 mark)
Mark this angle with some plasticine.
The plasticine should remain in place throughout the experiment to identify the refracting angle A.
d) Place one of the sheets of paper on the soft-board and fix it on the board with thumb pins placed at the corners.
e) Place the prism on one of its triangular faces on the upper third of the sheet of paper and draw its outline ABC. Remove the prism and draw a
normal NON' such that AO is about one third of AB. Draw also line DO making an angle i = DON=60°. See figure 4, Replace the prism on
its outline
Now fix two pins P1 and P2 on DO as upright as possible and as far apart as possible.
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f) View the pins through face AC and place pins P3 and P4 in line with the images of P 1 and P2 seen through the prism.
Fig 4
g)
Remove the prism from its outline. Join P3 to P4 and extend it to meet DOZ at Y. Note, D, O and Z are collinear. Measure angle ZYX=R.
Record its value in table 2.
Draw another outline of the prism in the middle third of the sheet of paper and repeat parts (c), (d) and (e) with other values of i on table 2
Record your values in table 2.
(6 marks)
Table 2
i°
R°
60
55
50
45
40
35
30
i) Plot a graph of R° against i° in figure 5.
j) Determine the minimum value Rmin of R.
k) Find V given that
l) Name of quantity V.
(3 marks)
(2 marks)
(3 marks)
(1 mark)
Page | 379
232/1,232/2,232/3 physics
MAARA FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/1
July/August - 2016
MARKING SCHEME
1.
0.2 × 50 = 10cm³
30.6 - 10
= 20.6cm³
2.
K = slope-1
= 22.22N/m
3.
direction in which this force acts.
SECTION B - 55 marks
14. a)
Sum of clockwise moments must be equal to sum of
anticlockwise moments.
Sum of downward forces must be equal to sum of
upward forces
ii) Stability increase. When ice melts the volume
deceases, this lowers the COG hence stability of the
beaker.
b) i) Volume of drop = volume of cylindrical film
3N
4.
Diffusion is faster with warm liquid because the
movement
of particles is faster due to increased energy.
5.
Clockwise moments = Anticlockwise moments.
ii) All salty acid drop forms a film
- All molecular are in contact with water as well as
themselves. any one.
15. a) Pressure applied at one part in a liquid is
transmitted equally to all other parts of the enclosed
liquid.
b) Pressure on B = Pressure of A
100 + 100 + 100 = 150 + 75w
150 = 75 w w = 2N
6.
Refinement of sound colour
mixing techniques.
7. It cannot be used to measure internal diameters
It has high inefficiency due to the screw.
8. Pressure law
9. Water level first rises then after sometime it falls. Since
contracts first.
After sometime the water contracts but a greater
10. The can crushed inwards then it regained its shape.
Shaking generate more steam in the can. The steam
generated causes arise in pressure in the can pushing
the wall of the can outward and shape was restored.
c) Low atmospheric pressure in places high above sea
level
- Leakages at the valves and pistons any one
d) Soapy water is an impurity, which reduces the
surface tension of water. The outside surface tension
pulls water apart.
16. a) i)
Q = m = 40 × 15 = 600 Joules
ii)
Q = MC
iii)
Q = MC
11.
iv)
12. The metal cylinder must be highly polished and heavily
lagged.
The two holes should be filled with a light oil to
improve thermal contact with the heater and the
thermometer.
13. The rate of change of momentum of a body is directly
proportional to the applied force and takes place in the
Heat lost by block = heat gained by water
and calorimeter
15C = 600 + 6300
b) Heat energy is conducted from the milk through the
wall of bottle. This heat energy is absorbed by the
water in the cloth which evaporate (latent heat of
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232/1,232/2,232/3 physics
vaporisation)
Less heat is absorbed by the water in bucket due to
convection hence slower cooling.
b)i) The centripetal force acting in the vertical position
is greater than the weight of the content in tin
ii) Angular velocity @
17.a)
19. a) Net resultant force is zero
or
Fv + U = mg
ii)- Friction
-
ii) F =
mg
Useless (wt of rope + bucket)
b)
18. a) State that when a body is totally or partially
immersed in fluid, it experiences an upthrust force
which is equal to the weight of the fluid displaced.
ii) Volume of water displaced
Weight of water
Weight of buoy
Upthrust = weight of displaced water.
Tension T = upthrust - weight of buoy
= 936 - 300
= 636N
b) i) Volume of a fixed mass of a gas is directly
proportional to absolute temperature provided that
pressure is kept constant.
ii) Neglecting the effect of the size of molecules of
the gas.
- Neglecting the presence of the inter-molecules
force
- Assumption of zero volume and pressure
c) Elastic collisions both KE and momentum are
conserved while
Inelastic collisions any momentum is conserved.
MAARA FORM FOUR JOINT EVALUATION
Kenya Certificate of Secondary Education
PHYSICS
Paper - 232/2
July/August - 2016
MARKING SCHEME
1.
i) Induction method
ii) Earthing to neutralise positive charges
1 mark CAO
1 mark correct
explanation
2.
1 mark 2 rays correctly
intersecting.
1 mark inverted image on
the screen
1 mark correctly labelled
diagram (atleast 2 parts)
3.
Resistance is the ratio of p.d., V across the ends of a conductor to the current, 1 passing through it.
4.- Convex mirror gives erect / upright image
Convex mirror has a wide field of view 1 mark any one correct
5. P = IV
100 = 250I
I = 0.04A
6. All fringes have coloured edges except the central one.
7. E = hf
1 mark
correction
definition.
1 mark substitution
1 mark correct observations
1 mark correct substitution
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232/1,232/2,232/3 physics
8. Electrons are ejected from the cathode by the radiation and are accelerated towards the anode hence completing the circuit.
1 mark correct explanation
9. The diode in (a) is forward biased while 9(b) is reverse biased.
The battery in 9(a) enhances flow of electrons across the barrier.
2 marks correct explanation
10.
1 mark correct formula
1 mark correct
substitution
1 mark correct answer with units
11. X-rays are produced when fast moving elections hit a metal target while gamma rays originate from disintegration of
nucleus of an atom.
1 mark correct explanation
12. Alpha
1 mark CAO
The path followed by the radiations is less curved / They have a large mass 1 mark any correct one mark
13.
1 mark formula
1 mark Substitution
SECTION B : 55 marks
14. a) i) To prevent the target from melting due to immense heat / to withstand very high temperatures. 1 mark
any correct
ii) - Higher boiling point than water 1 mark CAO
- Oil has a lower heat capacity than water
1 mark CAO
iii) - Lead has a high density 1 mark CAO
Increasing the heating current
1 mark CAO
b) i) A - Grid
1 mark CAO
B - Anode
1 mark CAO
ii) To deflect the cathode rays vertically
1 mark CAO
iii) Current heats up cathode and electrons are produced by thermionic emission
1 mark correct explanation
iv) Reduce collision / loss of K.E of cathode rays
1 mark any correct
- Prevent ionisation of gas in the CRT
15. a)i) Breaks the circuit instantaneously
1 mark
- Its economical since it is not replaced after overload or short circuit
1 mark
ii)
1 mark correct value of power
b)i) When the switch is closed, flux in the coil on the L.H.S grows and links the other coil thereby inducing E.M.F
When current is steady no flux changes and hence no current.
When the switch is opened the flux, collapses, hence inducing current in the opposite direction. 1 mark correct
Page | 382
232/1,232/2,232/3 physics
explanation
1 mark
1 mark correct explanation
1 mark correct definition
ii) Soft iron reduces losses due to hysteresis.
This is because it is easily magnetised and demagnetised.
16. a) i) Image that cannot be captured on the screen
ii)
1 mark two correctly drawn rays
1 mark correct location of the image
1 mark nature of the image
b)
iii) - Real
- Vertically inverted
- Larger than the object
- Formed beyond C
i)
1 mark
1 mark
any two correct.
1 mark formula
1 mark substitution
ii) Communication to transmit waves.
In medicine to view internal organs
iii)- Prisms do not absorb energy from incident radiation
- prism do not produce multiple images
- Prism do not tarnish or peel off like mirrors
17.a)i)
- Requires little attention to maintain 1 mark
- Large currents can be drawn from them over long period
ii) Gases are always produced during charging hence caps are opened for gassing.
b)
1 mark Any one correct
1 mark any two correct
1 mark
1 mark
1 mark
1 mark correct substitution
1 mark correct answer with units
ii) Total current
1 mark total current
Current divides in the ratio 1 : 2
correct
1 mark substitution
18. a)i) I.
M
1 mark CAO
II.
between L and M or N and M
1 mark any one correct
ii) E.M waves are waves which do not require material medium for transmission e.g. light waves while mechanical
waves are waves which require material medium for 1 mark correct example
Page | 383
232/1,232/2,232/3 physics
transmission e.g. sound waves.
b)
1.5  is proportional to 27.0cm
1= x
1 mark correct example
1 mark proportionality
1 mark correct substitution
= 18 cm
c) - Humidity
1 mark CAO
- Wind (drought)
1 mark CAO
19. a) i) rod XY moves towards right hand side
1 mark CAO
ii) When the wire is positioned at right angles to the magnet field
1 mark CAO
iii) No effect
1 mark CAO
iv) Increasing the current using weak magnet
1 mark any one correct
b) i) Attraction occurs between a magnet and magnetic material or between unlike poles of a magnet.
1 mark
ii)- Soft iron become an induced magnet and attracts the pin
1 mark
- Wood is non magnetic material hence does not attract the pin
1 mark