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CCC HOH FUK TONG COLLEGE
Mock Examination 2001-2002
Physics Paper II
Secondary: 5
Date: 26/03/2002
Time allowed: 1 hour
(11:15 – 12:15)
Max. Mark:
45
Instructions:
1.
Answer ALL QUESTIONS.
All the answers should be marked on the Answer Sheet.
2.
You should mark only ONE answer to each question.
NO MARKS.
3.
All questions carry equal marks. No marks will be deducted for wrong answers.
Two or more answers will score
****************************************************
There are 45 questions.
The last page of this question paper contains a list of physics formulae which you may find
useful.
If necessary, take g = 10 m s-2 . All cells are assumed to have negligible internal resistance.
1.
The given displacement-time
graph shows the motion of a
trolley for 5 seconds. The total
distance travelled is
A.
1.0 m
B.
2.0 m
C.
3.0 m
D.
6.0 m
2.
Which of the following statements about average speed and average velocity is/are
correct?
(1)
A body may have zero average velocity but non-zero average speed.
(2)
The average velocity of a body must be in the same direction as the
average speed.
(3)
Average speed must be larger than or equal to the magnitude of average
velocity.
A.
(1) only
B.
(2) and (3) only
C.
(1) and (3) only
D.
(1), (2) and (3)
P.2
3.
A little stone is dropped from rest from a cliff.
second.
A.
80 m
B.
45 m
C.
25 m
D.
20 m
B
3 kg
4.
S
A
2 kg
Find the distance travelled in the third
2N
In the above diagram, blocks A and B are connected by a light inextensible string and rest
on a smooth horizontal table. The masses of A and B are 2 kg and 3 kg respectively.
Block A is pulled by a force of 2 N. Find the tension in the string S.
A.
0.4 N
B.
0.8 N
C.
1.0 N
D.
1.2 N
5.
Load
20 N
A screw jack is used to lift a load of 4000 N by an effort of 20 N, as shown in the above
diagram. The pitch of the screw is 2  10-3 m and the length of the handle is 0.25 m.
Find the efficiency of the screw jack.
A.
9.9%
B.
25.5%
C.
50.9%
D.
62.5%
6.
1.5 cm
3.6 cm
The above paper tape is obtained from a trolley moving with uniform acceleration. The
frequency of the ticker-tape timer is 50 Hz. Find the acceleration of the trolley.
A.
0.21 m s-2
B.
0.70 m s-2
C.
0.73 m s-2
D.
1.05 m s-2
P.3
7.
P
0.8 m
Q
A pendulum bob is released from rest from a point P 0.8 m above its lowest position Q, as
shown in the above diagram. Neglecting air resistance, find the speed of the bob when
it reaches Q.
A.
4 m s-1
B.
8 m s-1
C.
16 m s-1
D.
It cannot be determined since the mass of the bob is not given
8.
Which of the following velocity-time graphs correctly shows the motion of a ping-pong
ball falling freely in a vacuum?
A.
B.
v
C.
D.
v
0
0
t
0
t
v
t
v
0
t
9.
A cannon ball is fired so that it hits the wall at the top of a 10 m tower. If the energy
needed to destroy the wall is 49 000 J and the mass of the cannon ball is 10 kg, the
minimum initial velocity of the cannon ball required to break the tower wall is
A.
100 m s-1
B.
200 m s-1
C.
300 m s-1
D.
400 m s-1
10.
A spring balance suspended from the ceiling of a lift registers the weight of a 20 kg body
as 150 N. The lift is probably
A.
stationary.
B.
ascending with uniform velocity.
C.
ascending with uniform acceleration.
D.
descending with uniform velocity.
P.4
11.
An escalator is said to be able to carry 120 passengers to a height of 10 m in one minute.
Assuming each passenger has a weight of 500 N, the possible power output by the
escalator must be at least
A.
1 000 W.
B.
5 000 W.
C.
10 000 W.
D.
50 000 W.
12.
An object is projected vertically upwards. Which of the following graphs correctly
describes the variation of its kinetic energy (KE) with height (h)?
A.
O
C.
O
D.
(3)
A.
B.
C.
D.
(2) only
(3) only
(2) and (3) only
(1), (2) and (3)
h
KE
h
A ray of light passes from air into a glass block.
is/are correct?
(Given that the critical angle of glass is 42.)
(1)
KE
h
KE
O
13.
B.
KE
O
h
Which of the following ray diagrams
(2)
P.5
14.
A concave lens is placed above the letter “d” which has the size shown in the above
diagram. The image of the letter “d” appears as
A.
B.
C.
D.
15.
A ray of light passes through layers of three materials labelled I, II, III as shown above.
The materials, not necessarily in order, are air (n = 1.0), water (n = 1.33) and glass (n =
1.5). The materials are
A.
B.
C.
D.
I
II
III
air
air
water
glass
water
glass
air
air
air
air
glass
water
16.
A fish in a tank of water looks through a thin glass wall at an object at position II as
shown above. The apparent position of the object will be at
A.
I.
B.
II.
C.
III.
D.
IV.
P.6
17.
Which of the following arrangements will enable an image of the object PQ to be formed
on a screen?
(1)
(2)
(3)
A.
B.
C.
D.
(1) only
(2) only
(1) and (3) only
(2) and (3) only
18.
A person having an eye defect finds that he can see distant objects more clearly under
water without wearing glasses. Which of the following statements are correct?
(1)
The focal length of the eye lens is longer when the person is under water
than when he is above water, with the eye muscles relaxed in both
situations.
(2)
The person is suffering from short sight.
(3)
In order to see clearly in air, he should wear diverging lenses.
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
19.
A metal block of mass 0.5 kg requires 5 000 J of heat to change its temperature from
20C to 30C. The specific heat capacity of the metal, in J kg-1 K-1, is
A.
400.
B.
1 000.
C.
5 000.
D.
250 000.
P.7
20.
The specific latent heat of vaporization of water is 2.26  106 J kg-1. It follows that
(1)
2.26  106 J of heat must be supplied to change 1 kg of water to steam at
its boiling point.
(2)
energy is required to pull the molecules further apart when water changes
from the liquid to gas state.
(3)
energy is required to increase the average kinetic energy of the molecules
when water boils.
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
21.
If 1 kg of ice at 0C and 1 kg of steam at 100C are mixed in an insulated container, the
result will be
(Given that: specific latent heat of fusion of ice = 3.34  105 J kg-1 ,
specific heat capacity of water = 4 200 J kg-1 C-1 ,
specific latent heat of vaporization of water = 2.26  106 J kg-1)
A.
a mixture of ice and water at 0C.
B.
water at 50C.
C.
a mixture of water and steam at 100C.
D.
steam at 100C.
22.
The pressure of a gas in a container
(1)
is produced by molecules hitting the walls of the container.
(2)
can be changed by changing the volume of the container.
(3)
depends on collisions between molecules in the gas.
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
23.
If the pressure of a gas is increased by 20% and its volume is decreased by 20%, its
temperature will
A.
increase by 6%.
B.
increase by 4%.
C.
remain unchanged.
D.
decrease by 4%.
24.
Which of the following is an application of ultra-violet radiation?
A.
Detecting cracks in railway tracks
B.
Detecting survivors buried in landslides
C.
Measurement of the depth of the sea-bed
D.
Sterilization of drinking water
25.
Which of the following statements about ultrasonic waves is correct?
A.
They are transverse waves.
B.
They are electromagnetic waves.
C.
They travel with a speed of 3  108 m s-1 in air.
D.
They cannot travel through a vacuum.
P.8
26.
A water wave travels towards the right. The diagram above shows the waveform at a
certain instant. Which of the following statements is/are true?
(1)
Particle P is moving downwards.
(2)
Particle Q is moving upwards.
(3)
Particle R is momentarily at rest.
A.
(3) only
B.
(1) and (2) only
C.
(2) and (3) only
D.
(1), (2) and (3)
Obstacle
27.
Shallow
region
Deep
region
The figure above shows a series of plane water waves travelling in a shallow region of
water. The waves pass through a small slit to a deep region of water. Which of the
following diagrams shows the wave pattern in the deep region?
28.
A.
B.
C.
D.
Given that the wavelengths of visible light range from 4  10-7 m to 7  10-7 m, which of
the following combinations of wavelengths for infrared, red and violet lights is possible?
Infrared
A.
B.
C.
D.
1  10 m
1  10-7 m
1  10-4 m
1  10-7 m
-4
Red light
7  10 m
7  10-7 m
4  10-7 m
4  10-7 m
-7
Violet light
4  10-7 m
4  10-7 m
7  10-7 m
7  10-7 m
P.9
29.
30.
Which of the following diagrams shows the electric field pattern formed by a positive
charge and a negative charge?
A.
B.
C.
D.
A light, conducting and negatively charged sphere is suspended
from an insulating thread. A positively charged metal plate is
brought near to the sphere as shown above. Which of the
following statements best describes the motion of the sphere?
A.
It moves away from the plate first and then moves back.
B.
It moves towards the plate, touches it and remains there.
C.
It moves towards the plate, touches it and then moves
away.
D.
It bounces to and fro on the plate.
31.
R2
R1
P
R3
R4
Q
In the above circuit, resistors R1, R2 and R3 all have a resistance of 1 . The equivalent
resistance across PQ is 1.75 . What is the resistance of resistor R4?
A.
1.5 
B.
2
C.
2.5 
D.
3
32.
In the above circuit, the power dissipated by the lamp is greater than that by the resistor.
Which of the following statements are correct?
(1)
The potential difference across the lamp is greater than that across the
resistor.
(2)
The current through the lamp is greater than that through the resistor.
(3)
The resistance of the lamp is less than that of the resistor.
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
P.10
33.
N
2
1
Q
P
A wire PQ is bent into a U shape and placed along the north-south direction as shown
above. Two compasses are placed at position 1 above the wire and at position 2
respectively. What will happen when a current flows from P to Q in the wire?
A.
B.
C.
D.
Compass 1 will
Compass 2 will
deflect anticlockwise
deflect clockwise
deflect clockwise
remain in the position shown
deflect clockwise
deflect anticlockwise
remain in the position shown
remain in the position shown
34.
N
S
Observer
A student observes the rotation of the coil in a motor as shown above, where the arrows
indicate the direction of current. Which of the following diagrams shows the direction
of forces acting on the two sides of the coil? ( and  represent current flowing into
and out of the plane of the paper respectively.)
A.
B.
C.
D.
35.
Soft iron bar
Coil P
Coil Q
S
The above diagram represents two coils P and Q wound on a soft iron bar. A deflection
of the centre-zero galvanometer is observed
A.
momentarily on closing switch S, but no deflection on opening it again.
B.
momentarily on opening switch S, but no deflection on closing it again.
C.
on closing switch S and for as long as it remains closed.
D.
momentarily on closing and opening switch S.
P.11
36.
An ideal transformer connected to the 220-V mains is used to supply current to a lamp
with rated values 20 W and 10 V. The secondary coil has 100 turns. What is the
current drawn from the mains and the number of turns in the primary?
A.
B.
C.
D.
Current
No. of turns in primary
0.09 A
0.09 A
2A
2A
100
2 200
100
2 200
37.
A1
R
A2
In the circuit shown above, the resistance of the light dependent resistor R decreases
when the intensity of light shining on it increases. What will happen to the readings of
the ammeters when bright light is shone on R?
A.
Both readings increase.
B.
A1 gets smaller and A2 stays the same.
C.
Both readings get smaller.
D.
A1 gets larger and A2 stays the same.
38.
Under which of the following conditions will the motor be switched on?
+5 V
LDR
A
B
M
0V
A.
B.
C.
D.
Light
Temperature
Bright
Dark
Bright
Dark
High
High
Low
Low
P.12
39.
R
S
1 k
+
P (1 V)
Q (5 V)
A galvanometer has a resistance of 1 k and a full scale deflection of 0.1 mA. The
above diagram shows how the galvanometer is converted into a voltmeter with a full
scale deflection of either 1 V at position P or 5 V at position Q. Find the resistances of
R and S.
A.
B.
C.
D.
Resistance of R
Resistance of S
9 k
9 k
9 k
10 k
40 k
49 k
50 k
40 k
40.
Which of the following items are sources of background radiation?
(1)
Outer space
(2)
Rocks
(3)
Radon gas in air
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
41.
The C-14 content in a 10-g sample of living wood gives a count rate of 200 per minute.
If the count rate due to C-14 content in a 10-g sample of ancient wood is 50 per minute,
what is the approximate age of the sample? (The half-life of C-14 is 5 700 years.)
A.
2 850 years
B.
5 700 years
C.
11 400 years
D.
22 800 years
P.13
Directions:
Each question below (Questions 42 – 45) consists of two statements. Decide
whether each of the two statements is true or false. If both are true, then decide
whether or not the second statement is a correct explanation of the first statement.
Then select one option A – D according to the following table:
A.
Both statements are true and the 2nd statement is a correct explanation of the
1st statement.
B.
Both statements are true and the 2nd statement is NOT a correct explanation
of the 1st statement.
C.
Only one statement is true while the other is false
D.
Both statements are false.
1st statement
2nd statement
42.
A convex lens can be used as a
magnifying glass.
The image of an object formed by a
convex lens is always magnified.
43.
When a ‘220 V, 100 W’ bulb P and a
‘220 V, 40 W’ bulb Q are connected in
series to a 220 V supply, the power
dissipated in P is larger than that in Q.
When a ‘220 V, 100 W’ bulb P and a
‘220 V, 40 W bulb Q are connected in
series to a 220 V supply, the current
passing through P is larger than that
through Q.
44.
The temperature of a pool of water
changes slowly even when the
temperature of the surroundings
changes rapidly.
Water has a high specific heat capacity.
45.
 sources are not suitable for injection
into human bodies as medical tracers.
 particles carry positive charges and
can be deflected by electric fields.
P.14
Useful Formulae in Physics
(a)
Relationships between initial velocity u, uniform acceleration a, final velocity v and
displacement travelled s after time t:
v=u+at
s=ut+ 1 at2
2
v2 = u2 + 2 a s
(b)
Potential energy gained by a body of mass m when raised through a height h is mgh.
(c)
Kinetic energy of a body of mass m moving with speed v is 1 mv2
2
(d)
Power = force  velocity
(e)
Equivalent resistance of two resistors R1 and R2 :
(f)
(i)
in series = R1 + R2
(ii)
in parallel =
R1 R2
R1  R2
Power = potential difference  current
~ ~ END OF PAPER ~ ~