HKCEE 1999 - 2003
PHYSICS - MC Questions
Heat
(1999-CE-PHY II - 16)
16.
Equal masses of liquids X, Y and Z are separately
heated. The above graph shows the variation of the
energies absorbed by the liquids with their
temperatures. Let CX, CY and CZ be the specific heat
capacities of X, Y and Z respectively. Which of the
following relations is correct ?
A.
B.
C.
D.
E.
CX =CY >CZ
CX =CY <CZ
CX >CY >CZ
CX >CY =CZ
CX <CY =CZ
(1999-CE-PHY II - 17)
17.
(1999-CE-PHY II - 18)
18. A cylinder contains a fixed mass of gas at a pressure
of 105 Nm-2 and a temperature of 27℃. The cylinder
is compressed to half of its original volume and the
pressure increases to 3 x 105 Nm-2. Find the final
temperature of the gas.
A.
B.
C.
D.
E.
The above apparatus is used to find the specific
latent heat of vaporization of a liquid. Which of the
following can improve the accuracy of the
experiment ?
A. wrapping the beaker with cotton wool
B. covering the beaker with a lid
C. stirring the liquid throughout the
experiment
D. using shorter wires to connect the heater
and the power supply
E. setting up a control experiment with the
heater not connected to the power supply
40.5℃
177℃
313.5℃
450℃
1527℃
(1999-CE-PHY II - 19)
19.
E.
X → E
(2000-CE-PHY II - 19)
19. A cup of fruit juice is of mass 0.2 kg and
temperature 70℃. If the specific heat capacity of the
fruit juice is 4000 Jkg-1K-1, find the minimum
amount of ice at 0℃ that should be added to the
juice in order to lower its temperature to 0℃.
(Note : Specific latent heat of fusion of ice = 3.34 x
105 J kg-1.)
Figure (a) shows a mechanical model of a gas and
Figure (b) shows the P-V relation of a fixed mass of
ideal gas at a certain temperature. If the operating
voltage of the motor in the model is increased,
which of the following denotes a corresponding
transition in the P-V graph (point X represents the
initial state of the gas) ?
A.
B.
C.
D.
X
X
X
X
→
→
→
→
A
B
C
D
A.
B.
C.
D.
E.
0.17 kg
0.20 kg
0.37 kg
0.84 kg
4.19 kg
(2000-CE-PHY II - 20)
20. Equal masses of five different liquids are separately
heated at the same rate. The initial temperatures of
the liquids are all 20℃. The boiling points and
specific heat capacities of the liquids are shown
below. Which one of them will boil first ?
Liquid
A.
B.
C.
D.
E.
P
Q
R
S
T
(2000-CE-PHY II - 21)
21.
Boiling point/ Specific heat capacity/ J
℃
kg-1K-1
50
1000
60
530
80
850
80
1710
360
140
The above apparatus is used to find the
specific latent heat of vaporization of water lv.
Which of the following factors will cause the result
obtained to be larger than the true value of lv ?
(1) Some energy is lost to the surroundings.
(2) Some steam condenses and drips back into
the beaker.
(3) Some boiling water inside the beaker
splashes out of the beaker.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
(2000-CE-PHY II - 22)
22. An object P has a higher temperature than another
object Q. Which of the following statements is/are
correct ?
(1) The internal energy of P must be higher than
that of Q.
(2) The specific heat capacity of P must be higher
than that of Q.
(3) There will be a heat flow from P to Q when
they are in contact.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
(2000-CE-PHY II - 23)
23.
The curve C in the above graph shows the P-V
relation of a fixed mass of ideal gas at a certain
temperature. Point X denotes the initial state of the
gas. The state of the gas is now changed along the
path shown from X to Y, then from Y to Z, and
finally from Z back to X along the curve C. Which
of the following statements is/are correct ?
(1)
The temperature of the gas remains unchanged
in the transition from X to Y.
(2) The temperature of the gas decreases in the
transition from Y to Z.
(3) The temperature of the gas remains unchanged
in the transition from Z to X.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
(2001-CE-PHY II - 16)
16. A melting ice block of mass 0.05 kg is mixed with x
kg of water at 0℃ in a well-insulated container. If
25 000 J of energy is supplied to the mixture, the
mixture changes to water at 4℃. Find the value of x.
(Given : specific latent heat of fusion of ice = 3.34
x 105 Jkg-1,
specific heat capacity of water = 4200 J
kg-1 K-1.)
A.
B.
C.
D.
E.
0.37
0.44
0.49
1.44
1.49
(2001-CE-PHY II - 17)
17.
C.
D.
E.
The above apparatus is used to measure the specific
heat capacity of a cylindrical copper block. The
result of the experiment is as follows:
Mass of copper block
Initial temperature
Final temperature
Initial joulemeter reading
Final joulemeter reading
= m kg
= 21℃
= 47℃
= R1 J
= R2 J
Which of the following expressions gives the
specific heat capacity of copper ( in J kg-1 K-1) ?
A.
B.
26m( R2  R1 )
R1  R2
26m
R2  R1
26m
m( R1  R2 )
26
m( R2  R1 )
26
(2001-CE-PHY II - 18)
18.
(2001-CE-PHY II - 19)
19. A cup of liquid P and a cup of liquid Q of equal mass
are heated at the same rate. It is found that the
temperature of P is rising at a rate faster than that of
Q. Which of the following deduction is/are correct ?
(1)
The figure above shows the cooling curve of a
substance which is initially in the liquid state. The
temperature of the substance remains unchanged
during the period PQ. Which of the following
statements about the substance during the period PQ
is/are correct ?
(1)
(2)
(3)
The substance is not losing any energy to the
surroundings.
Latent heat is absorbed by the substance.
The average potential energy of the molecules
of the substance is decreasing.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
(2)
(3)
P has a lower specific latent heat of
vaporization than Q
P has a lower boiling point than Q.
P has a lower specific heat capacity than Q.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
(2001-CE-PHY II - 20)
20.
The above apparatus is used to study the relation
between the pressure and temperature of a fixed
mass of gas at constant volume. Which of the
following can improve the accuracy of the
experiment ?
(1)
(2)
(3)
using a larger flask
using a shorter length of rubber tubing to
connect the gauge and the flask
setting up a control experiment with the burner
removed
A.
B.
(1) only
(3) only
C.
(1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
(2001-CE-PHY II - 21)
21.
The above graph shows the V-T relation of a fixed
mass of ideal gas. Point X denotes the initial state of
the gas. The gas changes its state from X to Y, then
from Y to Z and finally from Z back to X along the
path shown. Which of the following statements
about the pressure of the gas is/are correct ?
(1)
(2)
(3)
The pressure remains unchanged in the
transition from X to Y.
The pressure increases in the transition from Y
to Z.
The pressure decreases in the transition from Z
to X.
A.
B.
C.
(1) only
(3) only
(1) and (2) only
D.
E.
(2) and (3) only
(1), (2) and (3)
(2002-CE-PHY II - 19)
19.
A certain amount of crushed solid is heated and the
variation of its temperature with time is shown above.
If the same heater is used to heat a smaller amount of
the solid, which of the following graphs (in dash lines)
best shows the variation of the temperature of the
solid ?
(For Questions 20 and 21.) The specific heat capacity of
(in J kg-1 K-1).
a metal is measured using the following method:
(Given: Specific heat capacity of water
= 4200 J kg-1 K-1.)
A. 236
B. 381
C. 622
D. 953
A metal block is first immersed in boiling water for some
time. The block is then transferred to a cup of cold water.
(2002-CE-PHY II - 21)
After a while, the temperature of the water is measured.
21. The result obtained in Q.20 is found to be higher than
(2002-CE-PHY II - 20)
the true value of the specific heat capacity of the
20. The result of the experiment is as follows:
metal. Which of the following is a probable reason ?
A. Some hot water is still adhered to the metal
block when the block is transferred to the cold
Mass of metal block = 0.8 kg
water.
Mass of water in the cup = 0.3 kg
o
Initial temperature of water in the cup = 23 C
B. Some energy is lost to the surroundings when
Final temperature of eater in the cup = 38oC
the metal block is transferred to the cold
water.
Find the specific heat capacity of the metal
C. Some energy is absorbed by the cup.
D. The temperature of the metal block is still
(3) The intercept y0 denotes the absolute zero
higher than 38oC when the final temperature
temperature.
of the water in the cup is measured.
A. (1) only
B. (2) only
(2002-CE-PHY II - 22)
C. (1) and (3) only
22.
D. (2) and (3) only
(2002-CE-PHY II -23)
23.
The above graph shows the result obtained when an
experiment is performed to study the relation between
A column of gas is trapped inside a cylinder. The
the pressure and temperature of a fixed mass of gas at
piston is now pushed slowly causing the gas to be
constant volume. Which of the following statements
compressed at a constant temperature. Which of the
is/are correct?
following statements about the gas molecules in the
(1) The y- and x- axes denote the pressure and
cylinder is/are correct?
temperature of the gas respectively.
(2) The slope of the graph denotes the volume of the
gas.
(1) The average speed of the gas molecules increases.
(2) Each gas molecule exerts a greater impact force
on the walls of the cylinder in each collision.
(3) The gas molecules collide more frequently with
the walls of the cylinder.
A.
(1) only
B.
(3) only
C.
(1) and (2) only
D.
(2) and (3) only
(2003-CE-PHY II -19)
19. If there is no heat flow between two bodies when they are
in contact, then the two
bodies must have the same
A.
B.
C.
D.
temperature
internal energy
specific heat capacity
specific latent heat of vaporization
(2003-CE-PHY II -20)
20. The difference in absolute temperature of two bodies is
100 K. Express the temperature difference in degree
Celsius.
A.
B.
C.
D.
 173 C
100  C
273  C
373  C
D.
(2003-CE-PHY II -21)
21.
Its specific latent heat of vaporization can be
estimated by
1000t 2  t1 
m2  m1
(2003-CE-PHY II -22)
22.
A student uses an electric kettle to heat 0.5 kg of water at
20oC. The water boils in 4 minutes. Estimate the output
power of the kettle. The specific heat capacity of water is
4200J kg 1  C 1 .
As shown in Figure (a), some liquid in a beaker is heated by a
1000 W immersion heater. Figure (b) shows the variation of the
reading of the electronic balance with time t. Which of the
following statements about the liquid is incorrect?
A.
B.
C.
It starts to boil at t  t1
Its temperature increases during the period
t  0 to t1 .
Its specific heat capacity can be estimated by
1000t1
.
m2
A.
B.
C.
D.
175 W
700 W
875 W
1400 W
(2003-CE-PHY II -23)
23.
A tyre of a car is filled with air at a temperature of 20 oC
and a pressure of 200 kPa. After driving for some time,
the temperature of the air inside the tyre increases to 30 oC
and the capacity of the tyre increases by 1%. Find the
pressure inside the tyre.
A.
B.
C.
D.
188 kPa
205 kPa
273 kPa
297 kPa
(2003-CE-PHY II -24)
24.
The above apparatus is used to study the relation between the
pressure and volume of a fixed mass of gas at constant
temperature. Which of the following can improve the accuracy
of the experiment?
A.
B.
using a larger syringe
pushing the piston quickly
C.
using a longer length of rubber tubing
D. setting up a control experiment with the bourdon
gauge removed