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97 AL Physics/M.C./P.1
1997 Hong Kong Advanced Level Examination
AL Physics
Multiple Choice Question
1.
A.
A
B
F
B.
2.
2N
4N
6N
8N
10 N
v 2  u2
2g
C.
Two wooden blocks A and B are
connected by a string which passes over a
smooth, fixed pulley as shown. The
maximum friction between any two
surfaces is 2 N. If a horizontal force F is
applied to block B, find its minimum value
for moving B.
A.
B.
C.
D.
E.
v
g
vu
g
v 2  u2
g
E. It cannot be found as the vertical
distance fallen is not known.
D.
4.
centre
of mass
8m
O
A ball of mass m is projected vertically
downwards with speed v from a certain
height and rebounds from the ground back
to the same height.
Which of the
following statements is/are correct?
(Neglect air resistance.)
A
20º
The figure shows a car moving round a
corner with a radius of 8 m on a banked
road of inclination 20º. At what speed
would there be no fiction acting on the car
along OA?
(1) The collision between the ball and the
ground is not perfectly elastic.
(2) The loss in energy of the ball in the
collision is ½mv2.
(3) If the ball is projected vertically
upwards from the same height with
the same speed, it would rebound to a
greater height.
A.
B.
C.
D.
E.
5.0 m/s
5.2 m/s
5.4 m/s
5.6 m/s
5.8 m/s
5.
A.
B.
C.
D.
E.
3.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
A particle is projected horizontally from a
table with an initial speed u and attains a
speed v just before hitting the ground.
What is the time of flight of the particle?
(Neglect air resistance.)
A
h
A ball bearing is released from rest at a
height h on a smooth track and completes
the circular loop of the track. If R is the
reaction acting on the ball bearing at the
highest point A of the loop, which of the
97 AL Physics/M.C./P.2
following graphs correctly shows the
variation of R with h?
torque is now doubled, the flywheel will
acquire the same angular speed after 9 s.
Find the average frictional torque exerted
at the bearings of the flywheel.
A.
R
1
X
2
3
B.
X
7
7
C.
X
10
4
D.
X
7
1
E.
X
4
A.
0
h
B.
R
0
h
C.
R
0
8.
h
D.
R
0
A 50-g mass suspended from a light
helical spring oscillates with vertical
simple harmonic motion of amplitude 2.5
cm. If the maximum kinetic energy of the
mass is 3.0  10-3 J, its frequency of
oscillation is
A.
B.
C.
D.
E.
h
0.4 Hz
0.8 Hz
1.1 Hz
1.9 Hz
2.2 Hz
E.
R
0
6.
9.
h
A nucleus originally at rest splits into two
fragments of unequal mass. The fragment
with smaller mass has a larger
(1) momentum.
(2) speed.
(3) kinetic energy.
A.
B.
C.
D.
E.
7.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
A constant external torque X is applied to
a flywheel which is initially at rest. The
angular speed of the flywheel increases to
a certain value after 21 s. If the external
When a body performs a simple harmonic
motion, which of the following is/are
correct?
(1) Displacement from the equilibrium
position is /2 out of phase with the
velocity.
(2) Acceleration is /2 out of phase with
the velocity.
(3) Displacement from the equilibrium
position is in phase with the
acceleration.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
10. A low-altitude satellite near the earth’s
surface has a speed of 7.90 km/s. The
radius of the earth is about 4 times that of
the moon and the ratio of the average
density of the earth to that of the moon is
about 5 : 4. The speed of a low-altitude
satellite near the moon’s surface would be
97 AL Physics/M.C./P.3
A.
B.
C.
D.
E.
D. (2) and (3) only
E. (1), (2) and (3)
1.77 km/s
2.21 km/s
2.47 km/s
3.57 km/s
4.42 km/s
13. A beam of monochromatic light passes
through three media of refractive indexes
n1, n2 and n3 respectively as shown. The
boundaries between the media are parallel.
11.
S
T
n1
P
Q
n2
R
n3
The above figure shows a transverse wave
propagating to the right along a string. At
the moment shown, which of the labelled
particles has its velocity and acceleration
in opposite directions?
A.
B.
C.
D.
E.
P
Q
R
S
T
12.
incident pulse
Which of the following relations between
n1, n2 and n3 is correct?
A.
B.
C.
D.
E.
14. A moving ship sounds a foghorn and an
echo is received from a cliff behind it.
Which
of
the
following
wave
characteristics of the original sound is/are
different from that of the echo?
(1) frequency
(2) amplitude
(3) speed
Three identical long spiral springs are
connected respectively to a wall, a light
thread and a heavy spring. If a crestshaped pulse is sent along each spiral
spring towards the respective boundary,
which of the following diagrams correctly
show(s) the reflected pulse? (Transmitted
pulse is not shown.)
(1)
n1 > n3 > n2
n3 > n1 > n2
n1 > n2 > n3
n2 > n1 > n3
n3 > n2 > n1
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
15.
P
wall
X
(2)
light thread
light source
Y
screen
(3)
heavy spring
A. (1) only
B. (3) only
C. (1) and (2) only
In a Young’s double-slit experiment, light
of wavelength 400 nm is used. If the path
difference between the light from the two
slits X and Y to a point P on the screen is
3000 nm, which of the following is/are
correct?
(1) P is the 7th dark fringe.
97 AL Physics/M.C./P.4
(2) The fringe separation on the screen
increases if the light source is moved
closer to the slits.
(3) P becomes a bright fringe if light of
wavelength 500 nm is used.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
16. Two pipes A and B, with pipe A closed at
one end and pipe B open at both ends, are
sounded to give fundamental notes of the
same frequency. The length ratio of pipe
A to pipe B is
A.
B.
C.
D.
E.
1:4
1:2
1:1
2:1
4:1
17. In an arrangement for viewing Newton’s
rings, which of the following would be
observed if water is introduced to the
space between the lens and the glass plate?
A.
B.
C.
D.
E.
5 cm
10 cm
10 cm
5 cm
10 cm
less than 10 cm
less than 10 cm
10 cm
greater than 10 cm
greater than 10 cm
19. A plane transmission grating is placed at
the centre of a circular 0º - 360º
protractor. A beam of monochromatic
light is incident normally on the grating.
The zeroth-order maximum occurs at a
scale reading of 90º and a first-order
maximum occurs at a scale reading of 65º.
At what scale reading would a secondorder maximum be observed?
A.
B.
C.
D.
E.
148º
140º
130º
58º
40º
20. The diagram below shows the stress-strain
graphs up to the breaking point for two
cylindrical rods made from materials P
and Q respectively, which have the same
diameter and original length.
Q
tensile
stress
A. The rings disappear.
B. The central spot becomes bright.
C. The separation between the rings
increases.
D. The rings shift towards the centre.
E. There is no observable change.
P
0
18.
tensile strain
Which of the two materials
L2
L1
(1) is the more ductile
(2) exhibits greater stiffness
(3) has the greater strength?
O
10 cm
10 cm
10 cm
10 cm
The above diagram shows two light rays
from a point source O passing in turn
through a convex lens L1 and a concave
lens L2. Which of the following is true of
the focal lengths of the lenses?
Focal length of L1 Focal length of L2
A.
B.
C.
D.
E.
(1)
Q
P
Q
P
Q
(2)
P
Q
P
P
Q
(3)
Q
P
P
Q
P
21. Which of the following quantities can be
increased by increasing the voltage across
a metal wire?
(1) the average drift velocity of the
conduction electrons
97 AL Physics/M.C./P.5
(2) the number of conduction electrons
per unit volume
(3) the speed of the electrical signal
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.
22. A metal sphere is charged to a potential of
100 V. If the charge density on its surface
is 6.0  10-9 Cm-2, find the radius of the
sphere.
(Given: permittivity of free space = 8.85 
10-12 Fm-1)
A.
B.
C.
D.
E.
(2) to tune a radio to receive a certain
channel.
(3) to change the power factor of an a.c.
circuit.
0.04 m
0.15 m
0.21 m
0.35 m
0.60 m
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
25. Two cylindrical metal rods, X and Y, are
made from the same material and have the
same mass. The length of X is three times
that of Y. If currents of 1 A and 2 A pass
through X and Y respectively, the ratio of
the power dissipation in X to that in Y is
A.
B.
C.
D.
E.
9:1
1:4
9:2
3:4
9:4
23.
coil
S
N
to light beam galvanometer
The above figure shows a small coil,
connected to a light beam galvanometer,
placed in a region of uniform magnetic
field between the poles of a magnet. The
plane of the coil is parallel to the pole
faces. Which of the following actions
would produce a deflection of the
galvanometer?
(1) Moving the coil to and fro between
the poles.
(2) Moving the coil away from the region
between the pole faces.
(3) Rotating the coil about a diameter
through an angle of 180º.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
24. A variable capacitor can be used
(1) as the volume control of an amplifier.
26. A d.c. motor is connected to a source of
constant voltage V. When rotating at a
steady speed, the motor draws a current I
and the back e.m.f. developed in its
armature coil is . Which of the following
statements is/are correct?
(1) The resistance of the armature coil is
V/I.
(2) The mechanical power developed is
I.
(3) The back e.m.f.  increases with the
speed of rotation.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
27. Which of the following combinations of
physical quantities take(s) the unit of time?
(1) capacitance times resistance
(2) inductance divided by resistance
(3) capacitance times inductance
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
97 AL Physics/M.C./P.6
In the above circuit, the cell has an e.m.f.
6 V and negligible internal resistance. The
resistances of the four resistors R1, R2, R3
and R4 are 6 , 3 , 1  and 2 
respectively.
The capacitor has
capacitance 20 F. At steady state, the
charge on the capacitor plate connecting to
A is
28. A charged particle is accelerated across
the gap between two parallel metal plates
maintained at a certain potential difference
in a vacuum. Assuming there is no
gravitational force, the energy acquired by
the charged particle in crossing the gap
depends on
A. +40 C
B. +80 C
C.
0 C
D. -80 C
E. -40 C
(1) the mass of the charged particles.
(2) the width of the gap.
(3) the potential difference between the
plates.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
31.
A
B
D
C
29.
A
R
A cell of e.m.f. 1.5 V is connected in
series with a variable resistor of resistance
R and an ammeter A of resistance 0.5 .
By varying R, a series of ammeter
1
readings, I, are taken and a graph of
I
against R is plotted. The value of the yintercept is found to be 0.88 A-1. What is
the internal resistance of the cell?
A.
B.
C.
D.
E.
0.59 
0.82 
1.14 
1.20 
1.32 
A light rectangular wire frame ABCD
moves with a uniform speed to the left
across a region of uniform magnetic field
acting into paper. Which of the following
is/are true at the instant shown in the
figure?
(1) A current is flowing in the clockwise
direction.
(2) The electric potential at B is higher
than that at C.
(3) The side AD experiences a magnetic
force acting to the right.
A.
B.
C.
D.
E.
30.
A
R1
R2
C
R3
R4
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
32. A circuit is required for doubling the
amplitude of a sinusoidal alternating
voltage. Which of the following circuits
might be suitable?
(1)
B
6V
input
500
turns
output
1000
turns
97 AL Physics/M.C./P.7
C. 7.9  10-3 m3s-1
D. 1.0  10-2 m3s-1
E. 1.7  10-2 m3s-1
(2)
10 k
output
input
10 k
(3)
5 k
output
input
A.
B.
C.
D.
E.
35. Two different ideal gases, A and B, are
contained in two identical vessels. If the
ratio of their absolute temperature and the
ratio of the root-mean-square speed of the
molecules are respectively 2 : 1 and 3 : 1,
the ratio of their molecular mass is
A.
B.
C.
D.
E.
2:3
2:9
1:6
9:2
3:2
5 k
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
36. A fixed mass of an ideal gas undergoes a
cycle ABCD in which its pressure p and
volume V change as shown in the p-V
diagram below.
p
A
B
33. Only a small fraction of the electrical
energy supplied to a light bulb is
converted into light energy. Which of the
following explanations is/are correct?
(1) Energy is absorbed by the glass wall
of the bulb.
(2) The resistance of the filament of the
bulb is very high.
(3) Most of the energy is emitted as infrared radiation.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
34. In a horizontal pipeline of cross-sectional
area 2.5  10-3 m2, the static pressure and
total pressure at a certain point are 0.6 
104 Pa and 1.0  104 Pa respectively. The
fluid flowing through it is incompressible,
non-viscous and has a density of 1.2  103
kgm-3. The volume flow rate in the
pipeline is
A. 3.2  10-3 m3s-1
B. 6.5  10-3 m3s-1
D
0
C
V
Which of the following statements is/are
correct?
(1) From A to B, work is done by the gas.
(2) From B to C, heat is extracted from
the gas.
(3) From C to D, the internal energy of
the gas increases.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
37. When a gas is below its critical
temperature, which of the following is/are
correct?
(1) Intermolecular forces are significant.
(2) The gas can be liquefied by applying
pressure alone.
(3) Collisions between molecules are not
perfectly elastic.
97 AL Physics/M.C./P.8
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
40.
signal generator
A
38. The instantaneous value of an alternating
current I (in A) at time t (in s) is given by
the equation
I  2 2 sin 50t
Which of the following descriptions is/are
correct?
(1) The a.c. frequency is 50 Hz.
(2) The value of the current varies
between  2 2 A and  2 2 A.
(3) The r.m.s. value of the current is 2 A.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
R
C
In the above circuit, a signal generator of
fixed output voltage is connected in series
with a resistor R and a capacitor C. When
the frequency of the signal generator is
gradually increased, which of the
following is the correct variation of the
ammeter and voltmeter readings?
A.
B.
C.
D.
39.
E.
incident
monochromatic
radiation
Ammeter reading Voltmeter reading
increases
increases
throughout
throughout
increases
decreases
throughout
throughout
increases
increases and
throughout
then decreases
increases and
decreases
then decreases
throughout
increases and
decreases and
then decreases
then increases
C
A
d.c. source
A d.c. source is applied to a photocell as
shown.
Monochromatic radiation is
incident on cathode C so that
photoelectrons are emitted from the
cathode surface. The maximum kinetic
energy of the photoelectrons reaching
anode A can be increased by using
(1) a d.c. source of higher voltage.
(2) monochromatic radiation of longer
wavelength.
(3) the same monochromatic radiation but
higher of intensity.
A.
B.
C.
D.
E.
V
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
41. The transition of electrons between three
energy levels in a particular atom gives
rise to three spectral lines. The shortest
and longest wavelengths of those spectral
lines are 1 and 2 respectively. The
wavelength of the other spectral line is
A.
B.
C.
1   2
2
 2  1
1 2
1   2
D. (
1
1
 )1
1  2
E.
1 2
97 AL Physics/M.C./P.9
42.
45. In an experiment to determine the period
of oscillation, T, of a simple pendulum, the
time, t, for a number of complete
oscillations is taken. It is found that the
time for 30 complete oscillations is 28.7 
0.3 s. Which of the following statements
is/are correct?
+15 V
1 k
1 k
10 k
20 k
20 k
Vout
1 k
-15 V
In the above operational amplifier circuit,
the output voltage Vout is
A.
B.
C.
D.
E.
43.
-5 V
-2.5 V
0V
+2.5 V
+5 V
226
88 Ra is
one of the nuclides in the
uranium decay series. If the stable endproduct of this series is 206
82 Pb , the number
of -particles emitted between the
226
88 Ra stage and the end of the series is
A.
B.
C.
D.
E.
4
6
10
14
20
44. Which of the following statements about a
typical nuclear reactor in a power plant
is/are correct?
(1) The percentage of 235U isotope in fuel
rods is higher than that in natural
uranium.
(2) Boron-coated steel rods are used to
control the rate of neutron production.
(3) Pressurized water is used as coolant
inside the reactor core.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
(1) The reading error in t can be reduced
by counting 50 oscillations.
(2) The percentage error in T is the same
as that in t.
(3) The period T determined should be
quoted as 0.96  0.01 s.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
97 AL Physics/M.C./P.10
Question No.
Key
Question No.
Key
1.
2.
3.
4.
5.
C
C
D
C
E
26.
27.
28.
29.
30.
D
C
B
B
E
6.
7.
8.
9.
10.
D
E
E
C
A
31.
32.
33.
34.
35.
A
C
B
B
B
11.
12.
13.
14.
15.
E
D
B
C
B
36.
37.
38.
39.
40.
C
C
D
A
B
16.
17.
18.
19.
20.
B
D
D
A
A
41.
42.
43.
44.
45.
D
A
A
E
D
21.
22.
23.
24.
25.
A
B
D
D
E