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99-AL-PHY-II / p.1
1.
3.
Two objects A and B of equal mass m are
connected by two identical light springs and are
placed on a horizontal smooth surface. A horizontal
force F is applied to B so that the system is in
equilibrium. If the applied force F is suddenly
removed, what are the magnitudes of the
acceleration of each object at the instant when
force F is removed?
Acceleration of A
A.
zero
B.
zero
F
2m
F
m
F
m
C.
D.
E.
The above figure shows an open wagon moving
with negligible resistance in vertically falling rain.
An appreciable amount of rain falls into the wagon
and accumulates there,. What are the effects of the
accumulating rain on the speed, momentum and
kinetic energy of the wagon? (Ignore the effects of
the rain drops hitting the front of the wagon.)
Acceleration of B
Speed
F
m
zero
F
m
A.
B.
C.
D.
E.
zero
F
m
4.
2.
A.
B.
C.
D.
E.
0N
18 N
24 N
30 N
32 N
unchanged
unchanged
decreased
unchanged
increased
kinetic energy
decreased
unchanged
decreased
unchanged
increased
The velocity of an object changes with time but the
magnitude of its acceleration remains unchanged.
The motion of the object can be
(1)
(2)
(3)
A block of mass 5 kg is placed on the inclined
surface of the wedge shown above. All contact
surfaces are assumed to be smooth. What is the
magnitude of the horizontal force F exerted on the
wedge so that it remains stationary while the block
is sliding down the inclined surface with
acceleration ?
decreased
decreased
decreased
unchanged
unchanged
momentum
simple harmonic motion.
parabolic motion of a projectile.
uniform circular motion.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
5.
The above graph shows the variation of kinetic
energy E with the square of velocity v of a moving
mass m. What is the momentum of the mass when
it is moving at a speed of 2 ms 1 ?
A.
B.
C.
D.
E.
1 Ns
2 Ns
4 Ns
8 Ns
16 Ns
99-AL-PHY-II / p.2
6.
A light, rigid rod of length 1 m is hinged smoothly
at P at one end. Two small masses m and 2m are
fixed to the mid-point and the other end of the rod
respectively. The rod is held vertically above P and
is released from rest. What is the total rotational
energy of the system when the rod rotates to the
position vertically below P? (Neglect air
resistance)
A.
B.
C.
D.
E.
2.5 mg
4.5 mg
5 mg
7.5 mg
9 mg
9.
7.
3
A turntable of moment of inertia 1.0  10 kg m
is under the action of a torque. The variation of the
torque  acting about the axis of rotation with time
t is as shown. If the turntable is at rest initially,
what is its angular momentum at t = 20 s?
A.
B.
C.
40 kg m 2 s 1
100 kg m 2 s 1
200 kg m 2 s 1
D.
1 10 5 kg m 2 s 1
2  10 5 kg m 2 s 1
E.
2
8.
A small ball-bearing is projected with velocity v
from the lowest position P of a vertical circular
track which is not smooth. The ball-bearing starts
to leave the track at Q. Which of the following
diagrams best represents all the forces acting on
the ball-bearing at Q ?
The above graph shows the variation of the
acceleration a of a particle with its displacement x
from a fixed point. Which of the following graphs
shows the variation of its potential energy U with
x?
99-AL-PHY-II / p.3
10.
A converging light beam is directed towards a
convex mirror M. The reflected beam then passes
through a convex lens L and forms an image at I.
Which of the following about the focal lengths of
M and L is correct?
focal length of M
A.
4.8 
B.
5.2 
C.
5.6 
D.
6.0 
E.
6.4 
13. Two dippers S 1 and S 2 1.2 cm apart are attached to
a vibrator. They vibrate in phase in a ripple tank and
generate waves of wavelength 0.8 cm.
focal length of L
Which of the following statements is/are correct?
A.
B.
C.
D.
E.
more than 4 cm
less than 4 cm
4 cm
less than 4 cm
more than 4 cm
2cm
2 cm
2 cm
4 cm
4 cm
A.
B.
C.
D.
E.
12.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
In a Young’s double slit experiment, a
monochromatic light source of wavelength 700 nm
is used and the separation of the slits is 0.1 mm. If
15 bright fringes are observed, what is the angle
subtended by those fringes at the center of the
double slit?
S 1 and S 2 are positions of antinodes.
(2)
There is only one point between S 1 and S 2
which is always stationary.
The separation between two nearest
antinodes between S 1 and S 2 is 0.4 cm.
(3)
11. An astronomical refracting telescope is adjusted to
view a distant object under normal adjustment.
Which of the following statements is/are correct?
(1) The first image formed by the objective is real
and is smaller than the object.
(2) The final image formed by the eyepiece is at
the least distance of distinct vision from the
eye.
(3) If part of the objective is blocked by an
opaque obstacle, part of the final image could
not be viewed.
(1)
A.
B.
C.
D.
E.
14.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
On a straight road, a car and an ambulance move
with uniform speeds u 1 and u 2 respectively (with
u 2 > u 1 ) in the same direction. Initially the
ambulance is behind the car and it overtakes the
car after some time. The siren on the ambulance
continuously emits a sound of a certain frequency.
What is the ratio of the wavelength of sound
received by an observer in the car before the
ambulance overtakes to that after the ambulance
overtakes?
(Given : velocity of sound in air = v)
A.
v  u2
v  u2
B.
v  u2
v  u2
C.
u 2  u1
u 2  u1
D.
v  u 2  u1
v  u 2  u1
E.
v  u 2  u1
v  u 2  u1
99-AL-PHY-II / p.4
15. Students A and B are standing 5 m apart. A shouts to
B and the intensity level in db recorded by B is x. A
then walks away from B so that they are 10 m apart.
If A shouts again with the same power, what is the
intensity level in db recorded by B?
A.
B.
18.
A.
B.
1
x
4
1
x
2
C.
log 10
D.
E.
x 3
x6
Which of the following statements about a
communication satellite in parking orbit above the
earth’s surface is incorrect?
C.
D.
x
4
E.
It is accelerating towards the center of
the earth at all times.
It must be in circular orbit above the
earth’s equator.
It is always vertically above the same
place in the earth’s surface.
It must be rotating in the same sense
and with the same angular speed as the
earth.
It is at a height where its gravitational
potential energy is numerically equal
to its kinetic energy.
16.
19.
The above circuit can be used to find the resistance
of the resistor R. Which of the following
statements is/are correct?
(1)
(2)
(3)
The current passing through the ammeter is
in fact larger than that passing through R.
The ratio of voltmeter reading to ammeter
reading is in fact smaller than the resistance
R.
The circuit is suitable for measuring high
resistance.
A.
B.
C.
D.
E.
17.
In the above circuit, the battery has constant e.m.f.
and negligible internal resistance. If switch S is
closed, what would happen to the electric potential
at P and at Q?
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
Three resistors of resistance R 1 , R 2 and R 3 are
connected in parallel. It is known that R 1 >R 2 >R 3 .
The equivalent resistance of this combination is R.
Which of the following statements is/are correct?
(1) Energy dissipated in moving 1 C of charge
through the resistor of resistance R 1 is greater
than that through R 3
A.
B.
C.
D.
E.
20.
Potential at P
Potential at Q
increased
increased
unchanged
decreased
decreased
increased
decreased
unchanged
increased
decreased
Each of the following three students states a
conclusion after learning the formulae P = IV, P =
V 2 /R and P = I 2 R in electricity. Which of these
conclusion is/are correct?
(1) The power dissipated by any electric appliance
can be calculated from
P = IV
(2) The power dissipated by a kettle in inversely
proportional to its resistance as P = V 2 /R.
(3) The power consumed by a running motor
cannot be calculated from
P= I2 R
(2) R is smaller than R 2
(3) If the resistor with resistance R 1 is removed,
the resulting equivalent resistance is increased.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
99-AL-PHY-II / p.5
21.
Which of the following statements about electric
field lines is incorrect?
A.
B.
C.
D.
E.
22.
They are closest where the field is
strongest.
They are always perpendicular to
equipotential lines.
They always point from high electric
potential to low electric potential.
Work has to be done in moving an
electron along the direction of a field
line.
They tend to attract one another.
A capacitor is charged by a constant current.
Which of the following graphs shows the time
variation of the energy stored in the capacitor
during the charging process?
A charged capacitor of capacitance 47 F is
connected to a voltmeter. The voltmeter reading
drops from 8 V to 2 V in 7.8s. Find the resistance
of the voltmeter.
A.
B.
C.
D.
E.
23.
25.
60 k
80 k
120 k
166 k
240 k
26.
A resistance wire is connected across the terminals
of a battery. Which of the following statements is
incorrect?
A.
B.
C.
D.
E.
Before connection to the battery, the
conduction electrons in the wire move
randomly.
After connection to the battery, an electric
field is set up along the length of the wire.
The conduction electrons in the wire are
accelerated momentarily in the opposite
direction to that of the electric field.
The conduction electrons collide with one
another, giving out heat energy.
The current in the wire is proportional to the
average drift velocity of the electrons.
24.
Three capacitors are connected to a 45 V supply
as shown in the above circuit. The voltage at the
output is
A.
B.
C.
D.
E.
5V
15 V
30 V
36 V
40 V
In the above circuit, a capacitor is charged from a
battery E and then completely discharged through a
resistor R using a vibrating reed switch S. The
waveform displayed on the screen of the CRO with
suitable time base should be
99-AL-PHY-II / p.6
27.
Which of the following graphs correctly shows the
variation of the magnetic flux density B along the
axis of a long solenoid carrying a steady current
with its length l ?
(1)
(2)
(3)
A large e.m.f. is induced across coil L.
The neon lamp lights up momentarily.
Light bulb B continues to light up until the
neon lamp dies out.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
30.
28.
The figure show a long straight wire carrying an
a.c. current which lies on the plane of the paper.
When a small search coil is placed at B such that
the plane of the coil is on the paper, the length of
the trace on the CRO is 2 cm (with the time base of
the CRO switched off). If the search coil is moved
to A, the length of the trace would be
Which of the following products is/are measured in
joules?
(1)
(2)
(3)
A.
B.
C.
D.
E.
Boltzmann constant k times absolute
temperature T
Plank constant h times frequency v
Electronic charge e times potential difference
V
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
31.
For which of the following does the force between
two objects vary inversely as the square of the
distance between their centers?
(1)
(2)
29.
(3)
Two equal masses joined by a rubber band
under tension.
Two long straight parallel conducting wires
carrying steady electric currents.
The earth and a satellite in its orbit.
A.
B.
C.
D.
E.
In the above circuit, a coil L of large inductance, a
2 V light bulb B, a switch S and a 2 V battery are
connected in series. A neon lamp is connected
across L. Which of the following statements is/are
correct upon the opening of switch S?
0.5 cm
1 cm
2 cm
4 cm
8 cm
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
99-AL-PHY-II / p.7
32.
35.
The above figure shows an a.c. circuit in which a
variable resistor R is connected in series with an
air-cored inductor L of negligible resistance. The
a.c. supply has constant r.m.s. voltage and its
frequency can be varied. Which of the following
methods, on its own, can increase the r.m.s. voltage
across the variable resistor R?
(1)
(2)
(3)
Two long, straight, parallel conducting wires P and
Q are positioned as shown. The same current flows
through both wires and is directed into the plane of
the paper. Point A, B and C on the plane of the
paper are equidistant from both wires where C is
the mid-point between the wires. Which of the
following statements is/are correct?
Inserting an iron core in the inductor L.
Increasing the frequency of the a.c. supply.
Increasing the resistance of R.
(1)
A.
B.
C.
D.
E.
33.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and(3)
(2)
(3)
The following are energy values for hydrogen.
X
Y
Z
A.
B.
C.
D.
E.
Mean kinetic energy of hydrogen gas molecules
at room temperature
Ionization energy of a hydrogen atom
Photon energy of a particular line in the visible
emission spectrum of hydrogen
36.
Which of the following shows the correct
ascending order (the least first) of these energy
values?
A.
B.
C.
D.
E.
34.
The magnetic field strength at C is greater
than that at A.
The directions of the magnetic field at A and
at B are the same.
The magnetic field strength at B will
increase if the current flowing in the wires
increases.
A coil of metal wire is placed o a plane
perpendicular to a uniform magnetic field. The coil
is rotated through 180˚ about a diameter as shown.
X<Z<Y
X<Y<Z
Y<Z<X
Z<Y<X
Z<X<Y
When an electron in an atom falls from an excited
state to the ground state, which of the following
forms of radiation is not emitted?
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
The total charge circulated in the coil due to the
inducted current is independent of
infra-red
gamma-ray
ultra-violet
visible light
X-rays
A.
B.
C.
D.
E.
37.
the area of the coil.
the flux density of the magnetic field
the number of turns of the coil
the resistance of the coil
the time taken for the flux change.
99-AL-PHY-II / p.8
Two metallic containers X and Y of volume V and
4V respectively are connected by a narrow tube as
shown. Initially the tap S is closed and an ideal gas
is contained in X at a pressure of 400 kPa while
container Y is evacuated. The tap S is then opened
and when equilibrium is finally reached
A.
B.
C.
D.
E.
38.
than that at B.
B. No work is done by the gas when it
changes from A to B.
C. Work is done by the gas on the
surroundings when it changes from B to
C.
D. Heat energy is transferred to the gas
when it changes from A to B.
E. Heat energy is extracted from the gas
when it changes from B to C.
40.
the gas pressure in X is 100 kPa
there are still gas molecules moving
through the tap S.
the product of pressure and volume of
the gas in X is equal to that in Y.
the density of gas molecules in X is
greater than that in Y.
the gas molecules in Y on average
move faster than those in X.
The above graph shows the variation in maximum
kinetic energy K of photoelectrons with the
frequency f of the incident radiation on a metallic
surface. If radiation of twice the intensity is used,
which of the following graphs (dotted line) shows
the variation of K with f ?
Which of the following descriptions about ideal
gas is/are correct?
(1)
(2)
(3)
An ideal gas obeys Boyle’s law only under
high temperature and low pressure.
The molecules of an ideal gas have no size.
The internal energy of an ideal gas consists
of kinetic energy only.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
39.
A fixed mass of an ideal gas undergoes the process
ABC as shown in the pressure-temperature diagram.
Which of the following deductions from the
diagram is incorrect?
A. The volume of the gas at C is greater
41.
Three sinusoidal signals V 1 , V 2 and V 3 are
99-AL-PHY-II / p.9
applied in pairs to the X- and Y- inputs of a CRO
and the resulting Lissajous figures are as shown.
B.
C.
D.
E.
43.
Carbon-14 is radioactive and undergoes  –decay
with a half-life of about 5 600 years. A GM-tube
together with a scaler are used in an experiment to
determine the concentration of carbon-14 in a piece
of excavated wood. To find an accurate value for
the activity of the excavated wood, the
experimenter should
(1)
If V1 and V2 are applied to the X- and Y- inputs
respectively, the Lissajous figure should look like
(2)
(3)
prepare a sample of pure carbon-14 from the
piece of excavated wood.
take a count over as long a period of times as
possible.
take a second count without the presence of
the excavated wood.
A.
B.
C.
D.
E.
44.
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
Which of the following are reasonable estimates of
the density and volume of an adult human?
Density / kg m-3
A.
B.
C.
D.
E.
42.
45.
(2)
(3)
(1)
(2)
(3)
The heavy stable nuclides have more
neutrons than protons.
Unstable nuclides decay to produce new
nuclides closer to the shaded region.
Unstable nuclides above the shaded region
usually decay through  –emission.
A.
(1) only
1
0.1
0.1
0.01
0.01
Which of the following will give rise to a
systematic error in experimental measurement?
(1)
For stable nuclides, the number of neutrons N
when plotted against the number of protons Z
would give points lying within the above shaded
region. Which of the following statements is/are
correct?
100
100
1 000
1 000
10 000
Volume / m 3
using a slow-running stop watch in keeping
time
ignoring the background counts in
radioactive decay measurements
uncertainty in locating the sharpest image
position in an optics experiment
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)