Thermodynamics

1. On the Celsius scale the absolute zero of 12. ‘Stem Correction’ in platinum resistance
temperature is at thermometers are eliminated by the use of
[CBSE PMT 1994] (a) Cells (b) Electrodes
(a) 0°C (b) – 32°C (c) Compensating leads (d) None of the above
(c) 100°C (d) – 273.15°C 13. The absolute zero is the temperature at which
2. Oxygen boils at – 183°C. This temperature is [AIIMS 1998]
approximately
(a) Water freezes
[CPMT 1992]
(b) All substances exist in solid state
(a) 215°F (b) – 297°F
(c) Molecular motion ceases
(c) 329°F (d) 361°F
(d) None of the above
3. Recently, the phenomenon of superconductivity
has been observed at 95 K. This temperature is 14. Absolute scale of temperature is reproduced in
nearly equal to the laboratory by making use of a
[CPMT 1990] (a) Radiation pyrometer
(a) – 288°F (b) – 146°F (b) Platinum resistance thermometer
(c) – 368°F (d) +178°F (c) Constant volume helium gas thermometer
4. The temperature of a substance increases by 27°C. (d) Constant pressure ideal gas thermometer
On the Kelvin scale this increase is equal to[CPMT 1993]
15. Absolute zero (0 K) is that temperature at which
(a) 300 K (b) 2.46 K
[AFMC 1993]
(c) 27 K (d) 7 K
(a) Matter ceases to exist
5. The resistance of a resistance thermometer has
values 2.71 and 3.70 ohm at 10°C and 100°C. The (b) Ice melts and water freezes
temperature at which the resistance is 3.26 ohm (c) Volume and pressure of a gas becomes zero
is [CPMT 1994]
(d) None of these
(a) 40°C (b) 50°C
16. On which of the following scales of temperature,
(c) 60°C (d) 70°C the temperature is never negative
6. No other thermometer is as suitable as a platinum (a) Celsius (b) Fahrenheit
resistance thermometer to measure temperature
(c) Reaumur (d) Kelvin
in the entire range of
[MNR 1993]
17. The temperature on Celsius scale is 25°C. What is
the corresponding temperature on the Fahrenheit
(a) 0°C to 100°C (b) 100°C to 1500°C scale
(c) – 50°C to +350°C (d) – 200°C to 600°C [AFMC 2001]
(a) 40°F (b) 77°F
7. The temperature of the sun is measured with (c) 50°F (d) 45°F
[Pb. PMT 1998; CPMT 1998; Pb. PET 1997, 2001] 18. One quality of a thermometer is that its heat
(a) Platinum thermometer capacity should be small. If P is a mercury
thermometer, Q is a resistance thermometer and
(b) Gas thermometer
R thermocouple type then [CPMT 1997]
(c) Pyrometer
(a) P is best, R worst (b) R is best, P worst
(d) Vapour pressure thermometer
(c) R is best, Q worst (d) P is best, Q worst
8. Absolute temperature can be calculated by[AFMC 1994]
19. Two thermometers are used to record the
(a) Mean square velocity (b) Motion of the temperature of a room. If the bulb of one is
molecule wrapped in wet hanky
(c) Both (a) and (b) (d) None of the above [AFMC 1997]
9. Thermoelectric thermometer is based on (a) The temperature recorded by both will be
[CPMT 1993, 95; AFMC 1998] same
(a) Photoelectric effect (b) Seeback effect (b) The temperature recorded by wet-bulb
thermometer will be greater than that
(c) Compton effect (d) Joule effect
recorded by the other
10. Maximum density of H 2O is at the temperature
(c) The temperature recorded by dry-bulb
[CPMT 1996; Pb. PMT 1996] thermometer will be greater than that
(a) 32°F (b) 39.2°F recorded by the other

(c) 42°F (d) 4°F (d) None of the above

11. The study of physical phenomenon at low 20. The temperature of a body on Kelvin scale is
temperatures (below liquid nitrogen temperature) found to be x K. When it is measured by
is called [CPMT 1992]
Fahrenheit thermometer, it is found to be x°F,
then the value of x is
(a) Refrigeration (b) Radiation
[UPSEAT 2000; Pb. CET 2004]
(c) Cryogenics (d) Pyrometry

[Type text] Page 1

 Thermodynamics
(a) 40 (b) 313 [KCET 1998]

(c) 574.25 (d) 301.25 (a) Pyrometer (b) Thermometer

21. A centigrade and a Fahrenheit thermometer are (c) Bolometer (d) Calorimeter
dipped in boiling water. The water temperature is
29. The absolute zero temperature in Fahrenheit scale
lowered until the Fahrenheit thermometer
registers 140°. What is the fall in temperature as is
registered by the Centigrade thermometer [DCE 1996]
[CBSE PMT 1992; AIIMS 1998] (a) – 273°F (b) – 32°F
(a) 30° (b) 40° (c) – 460°F (d) – 132°F
(c) 60° (d) 80° 30. A constant pressure air thermometer gave a
22. At what temperature the centigrade (Celsius) and reading of 47.5 units of volume when immersed in
Fahrenheit, readings are the same ice cold water, and 67 units in a boiling liquids.
[RPMT 1997, 99, 2003; BHU 1997; MNR 1992; The boiling point of the liquid will be
DPMT 1998; CPMT 1995; UPSEAT 1999; KCET 2000] (a) 135°C (b) 125°C
(a) – 40° (b) + 40° (c) 112°C (d) 100°C
(c) 36.6° (d) – 37°
31. If a thermometer reads freezing point of water as
23. Standardisation of thermometers is obtained with 20°C and boiling point as 150°C, how much
[CPMT 1996] thermometer read when the actual temperature is
(a) Jolly’s thermometer 60°C [AFMC 2004]

(b) Platinum resistance thermometer (a) 98°C (b) 110°C

(c) Thermocouple thermometer (c) 40°C (d) 60°C
(d) Gas thermometer 32. If temperature of an object is 140°F, then its
24. The gas thermometers are more sensitive than temperature in centigrade is [
liquid thermometers because [CPMT 1993]
(a) 105°C (b) 32°C
(a) Gases expand more than liquids
(c) 140°C (d) 60°C
(b) Gases are easily obtained
33. Of the following thermometers, the one which can
(c) Gases are much lighter be used for measuring a rapidly changing
(d) Gases do not easily change their states temperature is a
25. Mercury thermometers can be used to measure [CPMT 1992]
temperatures upto (a) Thermocouple thermometer
[CBSE PMT 1992, 96; BHU 1998; UPSEAT 1998] (b) Gas thermometer
(a) 100°C (b) 212°C (c) Maximum resistance thermometer

(c) 360°C (d) 500°C (d) Vapour pressure thermometer

34. On centigrade scale the temperature of a body
26. A constant volume gas thermometer shows increases by 30 degrees. The increase in
pressure reading of 50cm and 90cm of mercury at temperature on Fahrenheit scale is
0°C and 100°C respectively. When the pressure (a) 50° (b) 40°
reading is 60 cm of mercury, the temperature is
(c) 30° (d) 54°
[MNR 1991; UPSEAT 2000; Pb. CET 2004]
35. The correct value of 0°C on Kelvin scale will be
(a) 25°C (b) 40°C [RPMT 1999]
(c) 15°C (d) 12.5°C (a) 273.15 K (b) 273.00 K
27. Mercury boils at 367°C. However, mercury (c) 273.05 K (d) 273.63 K
thermometers are made such that they can
measure temperature up to 500°C. This is done by
Thermal Expansion
[CPMT 2004]

(a) Maintaining vacuum above mercury column in 1. When a copper ball is heated, the largest
the stem of the thermometer percentage increase will occur in its

(b) Filling nitrogen gas at high pressure above the (a) Diameter (b) Area
mercury column (c) Volume (d) Density
(c) Filling nitrogen gas at low pressure above the 2. A vertical column 50 cm long at 50°C balances
mercury level another column of same liquid 60 cm long at
(d) Filling oxygen gas at high pressure above the 100°C. The coefficient of absolute expansion of
mercury column the liquid is [EAMCET 1990]
28. A device used to measure very high temperature (a) 0.005/°C (b) 0.0005/°C
is
(c) 0.002/°C (d) 0.0002/°C

[Type text] Page 2

 Thermodynamics
3. The apparent coefficient of expansion of a liquid 10. When a bimetallic strip is heated, it [CBSE PMT 1990]
when heated in a copper vessel is C and when (a) Does not bend at all
heated in a silver vessel is S. If A is the linear
(b) Gets twisted in the form of an helix
coefficient of expansion of copper, then the linear
(c) Bend in the form of an arc with the more
coefficient of expansion of silver is
expandable metal outside
[EAMCET 1991]
(d) Bends in the form of an arc with the more
C  S  3A C  3A  S expandable metal inside
(a) (b)
3 3
11. A solid ball of metal has a concentric spherical
S  3A C C  S  3A cavity within it. If the ball is heated, the volume
(c) (d)
3 3 of the cavity will
4. A uniform metal rod is used as a bar pendulum. If [AFMC 1997; Orissa PMT 2004]
the room temperature rises by 10°C, and the (a) Increase (b) Decrease
coefficient of linear expansion of the metal of the
–6 (c) Remain unaffected (d) None of these
rod is 2  10 per °C, the period of the pendulum
will have percentage increase of 12. A litre of alcohol weighs [AFMC 1994]

[NSEP 1992] (a) Less in winter than in summer

–3 –3
(a) – 2  10 (b) – 1  10 (b) Less in summer than in winter
–3 –3
(c) 2  10 (d) 1  10 (c) Some both in summer and winter
5. A bar of iron is 10 cm at 20°C. At 19°C it will be (
–6 (d) None of the above
of iron = 11  10 /°C) [EAMCET 1997]
–6 –6 13. 5 litre of benzene weighs [
(a) 11  10 cm longer (b) 11  10 cm shorter
–5 –5 (a) More in summer than in winter
(c) 11  10 cm shorter (d) 11  10 cm longer
(b) More in winter than in summer
6. When a rod is heated but prevented from
(c) Equal in winter and summer
expanding, the stress developed is independent of [EAMCET 1997]
(a) Material of the rod (b) Rise in temperature (d) None of the above
14. Water has maximum density at [
(c) Length of rod (d) None of above
(a) 0°C (b) 32°F
7. Expansion during heating [CBSE PMT 1994]
(c) – 4°C (d) 4°C
(a) Occurs only in solids
15. At some temperature T, a bronze pin is a little
(b) Increases the weight of a material large to fit into a hole drilled in a steel block. The
change in temperature required for an exact fit is
(c) Decreases the density of a material minimum when
(d) Occurs at the same rate for all liquids and [SCRA 1998]
solids (a) Only the block is heated
8. On heating a liquid of coefficient of cubical (b) Both block and pin are heated together
expansion  in a container having coefficient of (c) Both block and pin are cooled together
linear expansion  / 3, the level of liquid in the (d) Only the pin is cooled
container will [EAMCET 1993]
16. If the length of a cylinder on heating increases by
(a) Rise 2%, the area of its base will increase by [

(b) Fall (a) 0.5% (b) 2%

(c) Will remain almost stationary (c) 1% (d) 4%
3
(d) It is difficult to say 17. The volume of a gas at 20°C is 100 cm at normal
9. A pendulum clock keeps correct time at 0°C. Its pressure. If it is heated to 100°C, its volume
3
mean coefficient of linear expansions is  / C , becomes 125 cm at the same pressure, then
volume coefficient of the gas at normal pressure
then the loss in seconds per day by the clock if the
temperature rises by t°C is is [AFMC 1993]
[Pb. PET 2002; DPMT
2001]
1
 t  864000 1
(a) 0.0015/°C (b) 0.0045/°C
(a) 2 (b)  t  86400
t 2 (c) 0.0025/°C (d) 0.0033/°C
1
2 18. The coefficient of superficial expansion of a solid is
–5
1 1 2  10 /°C. It's coefficient of linear expansion is [
 t  86400  t  86400 –5 –5
(c) 2 (d) 2 (a) 4  10 /°C (b) 3  10 /°C
 t
2 t
1   1 –5
(c) 2  10 /°C
–5
(d) 1  10 /°C
2
 2 

[Type text] Page 3

 Thermodynamics
19. Density of substance at 0°C is 10 gm/cc and at
100°C, its density is 9.7 gm/cc. The coefficient of (a) x decreases, r and d increase
linear expansion of the substance will be
(b) x and r increase, d decreases
[BHU 1996; Pb. PMT 1999; DPMT 1998, 2003]
(a) 10
2
(b) 10
–2 (c) x, r and d all increase

(c) 10
–3
(d) 10
–4 (d) Data insufficient to arrive at a conclusion

20. Coefficient of real expansion of mercury is 0.18  28. The length of a metallic rod is 5m at 0°C and
–3 becomes 5.01 m, on heating upto 100°C. The
10 /°C. If the density of mercury at 0°C is 13.6
linear expansion of the metal will be
gm/cc. its density at 473K is [DPMT 1996]
–5 –5
(a) 2.33  10 /°C (b) 6.0  10 /°C
(a) 13.11 gm/cc (b) 26.22 gm/cc –5 –5
(c) 4.0  10 /°C (d) 2.0  10 /°C
(c) 52.11 gm/cc (d) None of these
29. A metal rod of silver at 0°C is heated to 100°C.
21. The real coefficient of volume expansion of It's length is increased by 0.19 cm. Coefficient of
glycerine is 0.000597 per°C and linear coefficient
cubical expansion of the silver rod is
of expansion of glass is 0.000009 per°C. Then the
–5 –5
apparent volume coefficient of expansion of (a) 5.7  10 /°C (b) 0.63  10 /°C
–5 –5
glycerine is [AIIMS 2000] (c) 1.9  10 /°C (d) 16.1  10 /°C
(a) 0.000558 per°C (b) 0.00057 per°C 30. A brass disc fits simply in a hole of a steel plate.
(c) 0.00027 per°C (d) 0.00066 per°C The disc from the hole can be loosened if the
system [UPSEAT 2001]
22. A beaker is completely filled with water at 4°C. It
will overflow if [EAMCET 1992; BHU 1994; AFMC 2005] (a) First heated then cooled (b)First cooled then heated
(a) Heated above 4°C (c) Is heated (d) Is cooled
(b) Cooled below 4°C 31. An iron bar of length 10 m is heated from 0°C to
(c) Both heated and cooled above and below 4°C 100°C. If the coefficient of linear thermal expansion
–6
respectively of iron is 10  10 /°C, the increase in the length of
(d) None of the above bar is [UPSEAT 2005]

23. The volume of a metal sphere increases by 0.24% (a) 0.5 cm (b) 1.0 cm
when its temperature is raised by 40°C. The
(c) 1.5 cm (d) 2.0 cm
coefficient of linear expansion of the metal is
.......... °C [Kerala PMT 2005] 32. If a cylinder of diameter 1.0 cm at 30°C is to be
(a) 2  10
–5
(b) 6  10
–5 solid into a hole of diameter 0.9997 cm in a steel
–5 –5
plate at the same temperature, then minimum
(c) 2.1  10 (d) 1.2  10 required rise in the temperature of the plate is :
24. Ratio among linear expansion coefficient (), (Coefficient of linear expansion of steel
areal expansion coefficient () and volume  12  10 6 / C ) [EAMCET 2001]
expansion coefficient () is [RPMT 2000]
(a) 25°C (b) 35°C
(a) 1 : 2 : 3 (b) 3 : 2 : 1
(c) 45°C (d) 55°C
(c) 4 : 3 : 2 (d) None of these
33. Surface of the lake is at 2°C. Find the temperature
25. If on heating liquid through 80°C, the mass of the bottom of the lake [
th
expelled is (1/100) of mass still remaining, the
(a) 2°C (b) 3°C
coefficient of apparent expansion of liquid is [RPMT 2004]
–4 –4 (c) 4°C (d) 1°C
(a) 1.25  10 /°C (b) 12.5  10 /°C
–5 34. Two rods, one of aluminum and the other made of
(c) 1.25  10 /°C (b) None of these
steel, having initial length l1 and l2 are connected
26. In cold countries, water pipes sometimes burst, together to form a single rod of length l1  l2 . The
because coefficients of linear expansion for aluminum and
(a) Pipe contracts steel are  a and  s respectively. If the length of
(b) Water expands on freezing each rod increases by the same amount when
their temperature are raised by t o C , then find the
(c) When water freezes, pressure increases
l1
ratio [IIT-JEE (Screening) 2003]
(d) When water freezes, it takes heat from pipes (l1  l2 )
27. A cylindrical metal rod of length L0 is shaped into s a
a ring with a small gap as shown. On heating the (a) (b)
a s
system
s a
X (c) (d)
( a   s ) ( a   s )

r Calorimetry
1. When vapour condenses into liquid [CPMT 1990]
d
[Type text] Page 4
 Thermodynamics
(a) It absorbs heat (b) It liberates heat 12. Heat required to convert one gram of ice at 0°C
(c) Its temperature increases (d) Itsinto steam at 100°C
temperature is (given Lsteam = 536 cal/gm)[Pb. PMT
decreases
2. At NTP water boils at 100°C. Deep down the mine, (a) 100 calorie (b) 0.01 kilocalorie
water will boil at a temperature (c) 716 calorie
[CPMT 1996] (d) 1 kilocalorie
(a) 100°C (b) > 100°C 13. 80 gm of water at 30°C are poured on a large
(c) < 100°C (d) Will not boil at all block of ice at 0°C. The mass of ice that melts is [
(a) 30 gm (b) 80 gm
3. If specific heat of a substance is infinite, it means
(c) 1600 gm (d) 150 gm
[AIIMS 1997]
14. The saturation vapour pressure of water at 100°C
(a) Heat is given out is
(b) Heat is taken in [EAMCET 1997]
(c) No change in temperature takes place whether (a) 739 mm of mercury (b) 750 mm of mercury
heat is taken in or given out (c) 760 mm of mercury (d) 712 mm of mercury
(d) All of the above 15. Two spheres made of same substance have
4. A gas in an airtight container is heated from 25°C diameters in the ratio 1 : 2. Their thermal
to 90°C. The density of the gas will capacities
[BCECEare1997]
in the ratio of
(a) Increase slightly (b) Increase [JIPMER 1999]
considerably (a) 1 : 2 (b) 1 : 8
(c) Remain the same (d) Decrease slightly (c) 1 : 4 (d) 2 : 1
5. A quantity of heat required to change the unit 16. Work done in converting one gram of ice at –10°C
mass of a solid substance, from solid state to into steam at 100°C is
liquid state, while the temperature remains [MP PET/PMT 1988; EAMCET (Med.) 1995; MP PMT 2003]
constant, is known as [AIIMS 1998]
(a) 3045 J (b) 6056 J
(a) Latent heat (b) Sublimation
(c) 721 J (d) 616 J
(c) Hoar frost (d) Latent heat of fusion
17. If mass energy equivalence is taken into account,
6. The latent heat of vaporization of a substance is
when water is cooled to form ice, the mass of
always
water should
[SCRA 1998]
[AIEEE 2002]
(a) Greater than its latent heat of fusion
(a) Increase (b) Remain unchanged
(b) Greater than its latent heat of sublimation
(c) Decrease (d) First increase then
(c) Equal to its latent heat of sublimation decrease
(d) Less than its latent heat of fusion 18. Compared to a burn due to water at 100°C, a burn
7. The factor not needed to calculate heat lost or due to steam at 100°C is [KCET 1999; UPSEAT 1999]
gained when there is no change of state is [AFMC 1997; BHU 1997]
(a) More dangerous (b) Less dangerous
(a) Weight (b) Specific heat
(c) Equally dangerous (d) None of these
(c) Relative density (d) Temperature change
19. 50 gm of copper is heated to increase its
8. 540 g of ice at 0°C is mixed with 540 g of water at temperature by 10°C. If the same quantity of heat
80°C. The final temperature of the mixture is[AFMC 1994] is given to 10 gm of water, the rise in its
(a) 0°C (b) 40°C temperature is (Specific heat of copper = 420
–1 –1
Joule-kg °C ) [EAMCET (Med.) 2000]
(c) 80°C (d) Less than 0°C
(a) 5°C (b) 6°C
9. Water is used to cool radiators of engines,
because (c) 7°C (d) 8°C
[AFMC 2001] 20. Two liquids A and B are at 32°C and 24°C. When
(a) Of its lower density (b) It is easily available mixed in equal masses the temperature of the
mixture is found to be 28°C. Their specific heats
(c) It is cheap (d) It has high specific
are in the ratio of [DPMT 1996]
heat
10. How much heat energy is gained when 5 kg of (a) 3 : 2 (b) 2 : 3
water at 20°C is brought to its boiling point (c) 1 : 1 (d) 4 : 3
–1 –1
(Specific heat of water = 4.2 kJ kg c ) [BHU 2001] 21. A beaker contains 200 gm of water. The heat
(a) 1680 kJ (b) 1700 kJ capacity of the beaker is equal to that of 20 gm of
(c) 1720 kJ (d) 1740 kJ water. The initial temperature of water in the
beaker is 20°C. If 440 gm of hot water at 92°C is
11. Melting point of ice [CBSE PMT 1993]
poured in it, the final temperature (neglecting
(a) Increases with increasing pressure radiation loss) will be nearest to [NSEP 1994]
(b) Decreases with increasing pressure (a) 58°C (b) 68°C
(c) Is independent of pressure
(c) 73°C (d) 78°C
(d) Is proportional to pressure

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 Thermodynamics
22. Amount of heat required to raise the temperature (a) Increases (b) Decreased
of a body through 1K is called its
(c) Remains unchanged (d) None of the above
[KCET 1996; MH CET 2001; AIEEE 2002]
31. By exerting a certain amountof pressure on an ice block, y
(a) Water equivalent (b) Thermal capacity
(a) Lower its melting point
(c) Entropy (d) Specific heat
(b) Make it melt at 0°C only
23. A metallic ball and highly stretched spring are
made of the same material and have the same (c) Make it melt at a faster rate
mass. They are heated so that they melt, the (d) Raise its melting point
latent heat required [AIIMS 2002]
32. When we rub our palms they gets heated but to a
(a) Are the same for both maximum temperature because
(b) Is greater for the ball (a) Heat is absorbed by our palm
(c) Is greater for the spring
(b) Heat is lost in the environment
(d) For the two may or may not be the same
depending upon the metal (c) Produced of heat is stopped
24. A liquid of mass m and specific heat c is heated to (d) None of the above
a temperature 2T. Another liquid of mass m/2 and 33. A bullet moving with a uniform velocity v, stops
specific heat 2c is heated to a temperature T. If suddenly after hitting the target and the whole
these two liquids are mixed, the resulting mass melts be m, specific heat S, initial
temperature of the mixture is temperature 25°C, melting point 475°C and the
latent heat L. Then v is given by
[EAMCET 1992]
[NCERT 1972]
(a) (2/3)T (b) (8/5)T
2
1 mv
(c) (3/5)T (d) (3/2)T (a) mL  mS (475  25 )  
2 J
25. Calorie is defined as the amount of heat required
mv 2
to raise temperature of 1g of water by 1°C and it (b) mS (475  25 )  mL 
2J
is defined under which of the following conditions
[IIT-JEE (Screening) 2005] mv 2
(c) mS (475  25 )  mL 
J
(a) From 14.5°C to 15.5°C at 760 mm of Hg
(b) From 98.5°C to 99.5°C at 760 mm of Hg mv 2
(d) mS (475  25 )  mL 
2J
(c) From 13.5°C to 14.5°C at 76 mm of Hg
34. A water fall is 84 metres high. If half of the
(d) From 3.5°C to 4.5°C at 76 mm of Hg
potential energy of the falling water gets
26. 100 gm of ice at 0°C is mixed with 100 g of water converted to heat, the rise in temperature of
at 100°C. What will be the final temperature of water will be [JIPMER 2002]
the mixture
(a) 0.098°C (b) 0.98°C
[SCRA 1996; AMU 1999]
(c) 9.8°C (d) 0.0098°C
(a) 10°C (b) 20°C
35. A body of mass 5 kg falls from a height of 30
(c) 30°C (d) 40°C metre. If its all mechanical energy is changed into
27. At atmospheric pressure, the water boils at 100°C. heat, then heat produced will be
If pressure is reduced, it will boil at [MP PMT
(a) 3501984]
cal (b) 150 cal
(a) Higher temperature (b) Lower temperature (c) 60 cal (d) 6 cal
(c) At the same temperature (d)At critical temperature36. In supplying 400 calories of heat to a system, the
28. A closed bottle containing water at 30°C is carried work done will be [MP PMT 1989]
to the moon in a space-ship. If it is placed on the
(a) 400 joules (b) 1672 joules
surface of the moon, what will happen to the
water as soon as the lid is opened (c) 1672 watts
[RPMT 2002] (d) 1672 ergs

(a) Water will boil 37. 0.93 watt-hour of energy is supplied to a block of
ice weighing 10 gm. It is found that
(b) Water will freeze
[NCERT 1973; DPMT 1999]
(c) Nothing will happen on it
(a) Half of the block melts
(d) It will decompose into H 2 and O 2
(b) The entire block melts and the water attains a
29. The thermal capacity of 40 gm of aluminium temperature of 4°C
(specific heat = 0.2 cal/gm/°C) is [CBSE
(c) The PMT
entire 1990]
block just melts
(a) 40 cal/°C (b) 160 cal/°C (d) The block remains unchanged
5
(c) 200 cal/°C (d) 8 cal/°C 38. The weight of a person is 60 kg. If he gets 10
30. If temperature scale is changed from °C to °F, the calories heat through food and the efficiency of
numerical value of specific heat will [CPMT 1984]

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 Thermodynamics
his body is 28%, then upto how much height he the rise in temperature of water would be (J = 4.3
can climb (approximately) Joule/cal)
[AFMC 1997] [Pb. PMT 2002]

(a) 100 m (b) 200 m (a) 42°C (b) 49°C

(c) 400 m (d) 1000 m (c) 0.49°C (d) 4.9°C
39. The temperature of Bhakhra dam water at the 47. A block of mass 100 gm slides on a rough
ground level with respect to the temperature at horizontal surface. If the speed of the block
high level should be decreases from 10 m/s to 5 m/s, the thermal
(a) Greater (b) Less energy developed in the process is
[UPSEAT 2002]
(c) Equal (d) 0°C
(a) 3.75 J (b) 37.5 J
40. The height of a waterfall is 84 metre. Assuming
that the entire kinetic energy of falling water is (c) 0.375 J (d) 0.75 J
converted into heat, the rise in temperature of the 48. 4200 J of work is required for
water will be (a) Increasing the temperature of 10 gm of water
through 10°C
(g  9.8 m / s 2 , J  4.2 joule / cal) [MP PET 1994]
(b) Increasing the temperature of 100 gm of
(a) 0.196°C (b) 1.960°C water through 10°C

(c) 0.96°C (d) 0.0196°C (c) Increasing the temperature of 1 kg of water

through 10°C
41. Hailstone at 0°C falls from a height of 1 km on an (d) Increasing the temperature of 10 kg of water
insulating surface converting whole of its kinetic through 10°C
energy into heat. What part of it will melt
49. At 100°C, the substance that causes the most
(g  10 m / s 2 ) [MP PMT 1994]
severe burn, is
1 1 [KCET 1999; UPSEAT 1999]
(a) (b)
33 8 (a) Oil (b) Steam
1
(c)  10  4 (d) All of it will melt (c) Water (d) Hot air
33
50. In a water-fall the water falls from a height of
42. The SI unit of mechanical equivalent of heat is 100 m. If the entire K.E. of water is converted into
[MP PMT/PET 1998] heat, the rise in temperature of water will be

(a) Joule  Calorie (b) Joule/Calorie (a) 0.23°C (b) 0.46°C

(c) Calorie  Erg (d) Erg/Calorie (c) 2.3°C (d) 0.023°C

43. Of two masses of 5 kg each falling from height of 51. A lead bullet of 10 g travelling at 300 m/s strikes
10 m, by which 2kg water is stirred. The rise in against a block of wood and comes to rest.
Assuming 50% of heat is absorbed by the bullet,
temperature of water will be [RPET 1997]
the increase in its temperature is
(a) 2.6°C (b) 1.2°C
(Specific heat of lead = 150J/kg, K) [EAMCET 2001]
(c) 0.32°C (d) 0.12°C (a) 100°C (b) 125°C
44. A lead ball moving with a velocity V strikes a wall (c) 150°C (d) 200°C
and stops. If 50% of its energy is converted into
52. The temperature at which the vapour pressure of
heat, then what will be the increase in
a liquid becomes equals to the external
temperature (Specific heat of lead is S)
(atmospheric) pressure is its
[RPMT 1996]
[Kerala (Engg.) 2001]
2 2
2V V
(a) (b) (a) Melting point (b) Sublimation point
JS 4 JS
(c) Critical temperature (d) Boiling point
V2 V 2S
(c) (d) 53. When the pressure on water is increased the
J 2J boiling temperature of water as compared to
45. The mechanical equivalent of heat J is[MP PET 2000] 100°C will be

(a) A constant (b) A physical quantity [RPET 1999]

(a) Lower
(c) A conversion factor (d) None of the above
(b) The same
46. Water falls from a height of 210m. Assuming
whole of energy due to fall is converted into heat (c) Higher
(d) On the critical temperature

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 Thermodynamics
54. Calorimeters are made of which of the following (c) kg C / J (d) J / kg C 2
[AFMC 2000]
64. 50 gm of ice at 0°C is mixed with 50 gm of water
(a) Glass (b) Metal at 80°C, final temperature of mixture will be [DCE 2002]
(c) Wood (d) Either (a) or (c) (a) 0°C (b) 40°C
55. Triple point of water is [CPMT 2002] (c) 40°C (d) 4°C
(a) 273.16°F (b) 273.16 K 65. The freezing point of the liquid decreases when
pressure is increased, if the liquid
(c) 273.16°C (d) 273.16 R
(a) Expands while freezing
56. A liquid boils when its vapour pressure equals
(b) Contracts while freezing
[MP PET 2002]
(c) Does not change in volume while freezing
(a) The atmospheric pressure
(d) None of these
(b) Pressure of 76.0 cm column of mercury
66. The relative humidity on a day, when partial
(c) The critical pressure pressure of water vapour is 0.012  10 5 Pa at 12°C
(d) The dew point of the surroundings is (take vapour pressure of water at this
temperature as 0.016  10 5 Pa )
57. The amount of work, which can be obtained by
supplying 200 cal of heat, is[Pb. PET 2001, 03; BHU 2004] [AIIMS 1998]
(a) 70% (b) 40%
(a) 840 dyne (b) 840 W
(c) 75% (d) 25%
(c) 840 erg (d) 840 J
67. A hammer of mass 1kg having speed of 50 m/s, hit
58. How many grams of a liquid of specific heat 0.2 at a iron nail of mass 200 gm. If specific heat of iron
a temperature 40°C must be mixed with 100 gm is 0.105 cal/gm°C and half the energy is converted
of a liquid of specific heat of 0.5 at a temperature into heat, the raise in temperature of nail is
20°C, so that the final temperature of the mixture (a) 7.1°C (b) 9.2°C
becomes 32°C [Pb. PET 1999] (c) 10.5°C (d) 12.1°C
(a) 175 gm (b) 300 g 68. Latent heat of 1gm of steam is 536 cal/gm, then
its value in joule/kg is [RPMT 1999]
(c) 295 gm (d) 375 g
(a) 2.25  10 6 (b) 2.25  10 3
59. 1 g of a steam at 100°C melt how much ice at 0°C?
(c) 2.25 (d) None
(Latent heat of ice = 80 cal/gm and latent heat of
69. Which of the following has maximum specific
steam = 540 cal/gm) [Pb. PET 2000]
heat
(a) 1 gm (b) 2 gm [RPMT 1999]
(c) 4 gm (d) 8 gm (a) Water (b) Alcohol
60. 5 g of ice at 0°C is dropped in a beaker containing (c) Glycerine (d) Oil
20 g of water at 40°C. The final temperature will 70. 50 gm ice at 0°C in insulator vessel, 50g water of
be [Pb. PET 2003] 100°C is mixed in it, then final temperature of the
mixture is (neglect the heat loss)
(a) 32°C (b) 16°C
(a) 10°C (b) 0  Tm  20 C
(c) 8°C (d) 24°C
(c) 20°C (d) Above 20°C
61. One kilogram of ice at 0°C is mixed with one
71. A stationary object at 4°C and weighing 3.5 kg
kilogram of water at 80°C. The final temperature falls from a height of 2000 m on a snow mountain
of the mixture is at 0°C. If the temperature of the object just before
hitting the snow is 0°C and the object comes to
(Take : specific heat of water  4200 J kg 1 K 1 ,
rest immediately (g  10 m / s 2 ) and (latent heat of
latent heat of ice  336 kJ kg 1 ) [KCET 2002]
ice  3.5  10 5 joule / sec ), then the object will melt
(a) 40°C (b) 60°C
(a) 2 kg of ice (b) 200 gm of ice
(c) 0°C (d) 50°C
(c) 20 gm ice (d) 2 gm of ice
62. During constant temperature, we feel colder on a 72. 300 gm of water at 25°C is added to 100 gm of ice
day when the relative humidity will be [Pb.
at 0°C. PMT
The 1996]
final temperature of the mixture is [MP PET 20
(a) 25% (b) 12.5% 5 5
(a)  C (b)  C
(c) 50% (d) 75% 3 2
(c) – 5°C (d) 0°C
63. Which of the following is the unit of specific heat
73. Calculate the amount of heat (in calories)
[MH CET 2004]
required to convert 5 gm of ice at 0°C to steam at
(a) J kg C 1 (b) J / kg C
100°C [DPMT 2005]

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 Thermodynamics
(a) 3100 (b) 3200 t
capacity 1.5 times, at a temperature of is added
3
(c) 3600 (d) 4200
to it, the resultant temperature will be
74. 2gm of steam condenses when passed through 4
(a) t (b) t
40gm of water initially at 25°C. The condensation 3
of steam raises the temperature of water to t 2
(c) (d) t
54.3°C. What is the latent heat of steam 2[J & K CET 2005] 3
(a) 540 cal/g (b) 536 cal/g 82. Dry ice is [CPMT 2000]
(a) Ice cube (b) Sodium chloride
(c) 270 cal/g (d) 480 cal/g
(c) Liquid nitrogen (d) Solid carbon dioxide
75. 10 gm of ice at 0°C is mixed with 100 gm of water
at 50°C. What is the resultant temperature of
mixture [AFMC 2005]

(a) 31.2°C (b) 32.8°C

(c) 36.7°C (d) 38.2°C

76. Three liquids with masses m1 , m 2 , m 3 are 1. A glass flask is filled up to a mark with 50 cc of
mercury at 18ºC. If the flask and contents are
thoroughly mixed. If their specific heats are
heated to 38ºC, how much mercury will be
c1 , c 2 , c 3 and their temperatures T1 , T2 , T3 –6
above the mark ? ( for glass is 9 × 10 /ºC and
respectively, then the temperature of the mixture coefficient of real expansion of mercury is 180
–6
is × 10 /ºC) [EAMCET 1997]

c 1 T1  c 2 T2  c 3 T3 (a) 0.85 cc (b) 0.46 cc

(a)
m 1c 1  m 2 c 2  m 3 c 3 (c) 0.153 cc (d) 0.05 cc

m 1 c 1 T1  m 2 c 2 T2  m 3 c 3 T3 2. The coefficient of apparent expansion of mercury

(b) –6
m 1c 1  m 2 c 2  m 3 c 3 in a glass vessel is 153 × 10 /ºC and in a steel
vessel is 144 × 10 /ºC. If  for steel is 12 × 10
–6 –

m 1 c 1 T1  m 2 c 2 T2  m 3 c 3 T3 6
/ºC, then that of glass is
(c)
m 1T 1  m 2 T 2  m 3 T3
[EAMCET 1997]

m 1 T1  m 2 T2  m 3 T3 –6
(a) 9 × 10 /ºC
–6
(b) 6 × 10 /ºC
(d)
c 1T 1  c 2 T 2  c 3 T 3 –6
(c) 36 × 10 /ºC
–6
(d) 27 × 10 /ºC
77. The point on the pressure temperature phase 3. Solids expand on heating because [
diagram where all the phases co-exist is called[MH CET 2005]
(a) Kinetic energy of the atoms increases
(a) Sublimation (b) Fusion point
(b) Potential energy of the atoms increases
(c) Triple point (d) Vaporisation point
(c) Total energy of the atoms increases
78. Boiling water is changing into steam. At this stage
(d) The potential energy curve is asymmetric
the specific heat of water is [UPSEAT 1998]
about the equilibrium distance between
(a) < 1 (b)  neighbouring atoms

(c) 1 (d) 0 4. An iron tyre is to be fitted on to a wooden wheel

1m in diameter. The diameter of tyre is 6 mm
79. A vessel contains 110 g of water. The heat
smaller than that of wheel. The tyre should be
capacity of the vessel is equal to 10 g of water.
heated so that its temperature increases by a
The initial temperature of water in vessel is 10°C.
minimum of (the coefficient of cubical expansion
If 220 g of hot water at 70°C is poured in the –5
of iron is 3.6 × 10 /ºC) [CPMT 1989]
vessel, the final temperature neglecting radiation
loss, will be [UPSEAT 2000] (a) 167ºC (b) 334ºC

(a) 70°C (b) 80°C (c) 500ºC (d) 1000ºC

(c) 60°C (d) 50°C 5. A glass flask of volume one litre at 0°C is filled,
level full of mercury at this temperature. The
80. The thermal capacity of a body is 80 cal, then its flask and mercury are now heated to 100°C. How
water equivalent is [UPSEAT 2001]
much mercury will spill out, if coefficient of
(a) 80 cal / gm (b) 8 gm volume expansion of mercury is 1.82  10 4 / C and
(c) 80 gm (d) 80 kg linear expansion of glass is 0.1  10 4 / C
81. A liquid of mass M and specific heat S is at a
respectively [MNR 1994]
temperature 2t. If another liquid of thermal
(a) 21.2 cc (b) 15.2 cc
[Type text] Page 9
 Thermodynamics
–5 –5
(c) 1.52 cc (d) 2.12 cc (a) 3.316 × 10 /ºC (b) 2.316 × 10 /ºC
–5
6. A steel scale measures the length of a copper wire (c) 4.316 × 10 /ºC (d) None of these
as 80 .0 cm, when both are at 20 C (the calibration 12. It is known that wax contracts on solidification. If
temperature for scale). What would be the scale molten wax is taken in a large vessel and it is
read for the length of the wire when both are at allowed to cool slowly, then
40 C ? (Given steel  11  10 6 per°C and copper (a) It will start solidifying from the top
 17  10 6 per C ) downward
[CPMT 2004] (b) It will start solidifying from the bottom
(a) 80 .0096 cm (b) 80 .0272 cm upward

(c) 1 cm (d) 25 .2 cm (c) It will start solidifying from the middle,

upward and downward at equal rates
7. A bimetallic strip is formed out of two identical
(d) The whole mass will solidify simultaneously
strips, one of copper and other of brass. The
coefficients of linear expansion of the two metals 13. A substance of mass m kg requires a power input
are  C and  B . On heating, the temperature of of P watts to remain in the molten state at its
the strip goes up by T and the strip bends to melting point. When the power is turned off, the
form an arc of radius of curvature R. Then R is sample completely solidifies in time t sec. What is
[IIT-JEE (Screening) 1999] the latent heat of fusion of the substance
(a) Proportional to T [IIT JEE 1992]

(b) Inversely proportional to T (a)

Pm
(b)
Pt
t m
(c) Proportional to |  B   C |
m t
(d) Inversely proportional to |  B   C | (c) (d)
Pt Pm
8. Two metal strips that constitute a thermostat 14. Steam at 100ºC is passed into 1.1 kg of water
must necessarily differ in their contained in 1992]
[IIT-JEE a calorimeter of water equivalent
(a) Mass 0.02 kg at 15ºC till the temperature of the
calorimeter and its contents rises to 80ºC. The
(b) Length
mass of the steam condensed in kg is
(c) Resistivity [IIT 1995]
(d) Coefficient of linear expansion (a) 0.130 (b) 0.065
9. A metal ball immersed in alcohol weighs W1 at (c) 0.260 (d) 0.135
0°C and W2 at 59°C. The coefficient of cubical
15. 2 kg of ice at – 20°C is mixed with 5 kg of water at
expansion of the metal is less than that of alcohol. 20°C in an insulating vessel having a negligible
Assuming that the density of metal is large
heat capacity. Calculate the final mass of water
compared to that of alcohol, it can be shown that
remaining in the container. It is given that the
[CPMT 1998]
specific heats of water and ice are 1 kcal/kg per °C
(a) W1  W2 (b) W1  W2 and 0.5 kcal/kg/°C while the latent heat of fusion
(c) W1  W2 (d) W2  (W1 / 2) of ice is 80 kcal/kg [IIT-JEE (Screening) 2003]

(a) 7 kg (b) 6 kg
10. The coefficient of volumetric expansion of
mercury is (c) 4 kg (d) 2 kg
–5
18 × 10 /ºC. A thermometer bulb has a volume
–6 3 2 16. Water of volume 2 litre in a container is heated
10 m and cross section of stem is 0.004 cm .
with a coil of 1 kW at 27 C . The lid of the
Assuming that bulb is filled with mercury at 0ºC
then the length of the mercury column at 100ºC is container is open and energy dissipates at rate of
[Pb. PMT 1998, DPMT 1997, 2001] 160 J / s. In how much time temperature will rise

(a) 18.8 mm (b) 9.2 mm from 27 C to 77 C [Given specific heat of water

is 4.2 kJ / kg ] [IIT-JEE (Screening) 2004]
(c) 7.4 cm (d) 4.5 cm
11. A piece of metal weight 46 gm in air, when it is (a) 8 min 20 s (b) 6 min 2 s
immersed in the liquid of specific gravity 1.24 at (c) 7 min (d) 14 min
27ºC it weighs 17. A lead bullet at 27°C just melts when stopped by
30 gm. When the temperature of liquid is raised an obstacle. Assuming that 25% of heat is
to 42ºC the metal piece weight 30.5 gm, specific absorbed by the obstacle, then the velocity of the
gravity of the liquid at 42ºC is 1.20, then the bullet at the time of striking (M.P. of lead =
linear expansion of the metal will be 327°C, specific heat of lead = 0.03 cal/gm°C,
[BHU 1995]

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 Thermodynamics
latent heat of fusion of lead = 6 cal/gm and J = 4.2 (c)  1  2 2 (d) None of these
joule/cal) [IIT 1981]
23. Three rods of equal length l are joined to form an
(a) 410 m/sec (b) 1230 m/sec equilateral triangle PQR. O is the mid point of PQ.
Distance OR remains same for small change in
(c) 307.5 m/sec (d) None of the above
temperature. Coefficient of linear expansion for
18. If two balls of same metal weighing 5 gm and 10 PR and RQ is same i.e.  2 but that for PQ is  1 .
R
gm strike with a target with the same velocity. Then
The heat energy so developed is used for raising (a)  2  3 1
their temperature alone, then the temperature
(b)  2  4 1
will be higher
(a) For bigger ball (c)  1  3 2 P Q
O
(b) For smaller ball (d)  1  4 2

(c) Equal for both the balls 24. A one litre glass flask contains some mercury. It is
found that at different temperatures the volume of
(d) None is correct from the above three
air inside the flak remains the same. What is the
19. The temperature of equal masses of three volume of mercury in this flask if coefficient of
–6
different liquids A, B and C are 12ºC, 19ºC and linear expansion of glass is 9  10 /°C while of
–4
28ºC respectively. The temperature when A and B volume expansion of mercury is 1.8  10 /°C
are mixed is 16ºC and when B and C are mixed is (a) 50 cc (b) 100 cc
23ºC. The temperature when A and C are mixed is
(c) 150 cc (d) 200 cc
[Kerala PET 2005]
25. 10 gm of ice at – 20°C is dropped into a calorimeter
(a) 18.2ºC (b) 22ºC
containing 10 gm of water at 10°C; the specific
(c) 20.2ºC (d) 25.2ºC heat of water is twice that of ice. When
20. In an industrial process 10 kg of water per hour is equilibrium is reached, the calorimeter will
to be heated from 20°C to 80°C. To do this steam at contain
150°C is passed from a boiler into a copper coil (a) 20 gm of water
immersed in water. The steam condenses in the
(b) 20 gm of ice
coil and is returned to the boiler as water at 90°C.
how many kg of steam is required per hour. (c) 10 gm ice and 10 gm water
(d) 5 gm ice and 15 gm water
(Specific heat of steam = 1 calorie per gm°C, Latent
heat of vaporisation = 540 cal/gm) 26. A rod of length 20 cm is made of metal. It expands
by 0.075cm when its temperature is raised from
(a) 1 gm (b) 1 kg
0°C to 100°C. Another rod of a different metal B
(c) 10 gm (d) 10 kg having the same length expands by 0.045 cm for
21. In a vertical U-tube containing a liquid, the two the same change in temperature. A third rod of
arms are maintained at different temperatures t 1 the same length is composed of two parts, one of
and t 2 . The liquid columns in the two arms have metal A and the other of metal B. This rod
expands by 0.060 cm for the same change in
heights l1 and l 2 respectively. The coefficient of
temperature. The portion made of metal A has the
volume expansion of the liquid is equal to length [CPMT 1991]
t1
t2
(a) 20 cm (b) 10 cm
l1
(c) 15 cm (d) 18 cm
l2
27. Steam is passed into 22 gm of water at 20°C. The
mass of water that will be present when the
l1  l 2 l1  l 2 water acquires a temperature of 90°C (Latent
(a) (b)
l 2 t 1  l1 t 2 l1 t 1  l 2 t 2 heat of steam is 540 cal/gm) is

l1  l 2 l1  l 2 [SCRA 1994]
(c) (d)
l 2 t 1  l1 t 2 l1 t 1  l 2 t 2 (a) 24.8 gm (b) 24 gm

22. The coefficient of linear expansion of crystal in (c) 36.6 gm (d) 30 gm

one direction is  1 and that in every direction
perpendicular to it is  2 . The coefficient of
cubical expansion is
(a)  1   2 (b) 2 1   2

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 Thermodynamics
1. The graph AB shown in figure is a plot of (d) Change from gaseous state to liquid state
temperature of a body in degree celsius and
5. The figure given below shows the cooling curve of
degree Fahrenheit. Then
pure wax material after heating. It cools from A
B to B and solidifies along BD. If L and C are
100°C
respective values of latent heat and the specific
Centigrad
heat of the liquid wax, the ratio L/C is
e Y
T°C A
32° F 212°F
A 90
Fahrenheit
B D
80
(a) Slope of line AB is 9/5 (b)Slope of line AB is 5/9 2 4
min min X
(c) Slope of line AB is 1/9 (d)Slope of line AB is 3/9 Time
(Min.)
2. The graph shows the variation of temperature (T) (a) 40 (b) 80
of one kilogram of a material with the heat (H)
(c) 100 (d) 20
supplied to it. At O, the substance is in the solid
state. From the graph, we can conclude that 6. A solid substance is at 30°C. To this substance
T heat energy is supplied at a constant rate. Then
C (H3,T2)  temperature versus time graph is as shown in the
D (H4,T2)
figure. The substance is in liquid state for the
A(H1,T1)  portion (of the graph) [RPET
240 F 1990, 94]

Temperature
 B(H2,T1)
210 D

(T°C)
O H B E
60
C
(a) T 2 is the melting point of the solid 30
A Time
(b) BC represents the change of state from solid
to liquid
(a) BC (b) CD
(c) (H 2  H1 ) represents the latent heat of fusion
of the substance (c) ED (d) EF

(d) (H 3  H1 ) represents the latent heat of 7. The variation of density of water with
vaporization of the liquid temperature is represented by the

3. A block of ice at –10°C is slowly heated and (a) (b)

Density

converted to steam at 100°C. Which of the following curves represents the phenomenon qualitatively [IIT-JEE (Scre
Density

(a) (b)
Temperatu

Temperatu

Temperatur
re

re

e Temperatur
(c) (d)
e
Density

Density

Heat Heat
supplied supplied
(c) (d)
Temperatu

Temperatu

Temperatur Temperatur
e e
re

re

8. If a graph is plotted taking the temperature in

Fahrenheit along Y-axis and the corresponding
temperature in Celsius along the X-axis, it will be
Heat Heat a straight line [AIIMS 1997]
supplied supplied
4. The portion AB of the indicator diagram (a) Having a +ve intercept on Y-axis
representing the state of matter denotes (b) Having a +ve intercept on X-axis
P A (c) Passing through the origin

C (d) Having a – ve intercepts on both the axis

B 9. Which of the curves in figure represents the
D relation between Celsius and Fahrenheit
V temperatures
(a) The liquid state of matter °C
(b) Gaseous state of matter (a) 1
2 3
(c) Change from liquid to gaseous state (b) 2
°F

[Type text] 4 1 Page 12

 Thermodynamics
(c) 3 (c) C (d) All have equal specific
heat
(d) 4
14. Two substances A and B of equal mass m are
10. Heat is supplied to a certain homogenous sample –1
heated at uniform rate of 6 cal s under similar
of matter, at a uniform rate. Its temperature is
plotted against time, as shown. Which of the conditions. A graph between temperature and
following conclusions can be drawn time is shown in figure. Ratio of heat absorbed
Temperatu H A / H B by them for complete fusion is
re
9
(a)
10

Temperature
4 A
0
80
4
Time (b)

°C
60
9 40 B

(a) Its specific heat capacity is greater in the solid 8 20

(c)
state than in the liquid state 5
0 1 2 3 4 5 6 7
(b) Its specific heat capacity is greater in the 5
(d)
liquid state than in the solid state 8
(c) Its latent heat of vaporization is greater than
its latent heat of fusion
(d) Its latent heat of vaporization is smaller than
its latent of fusion
11. A student takes 50gm wax (specific heat = 0.6
kcal/kg°C) and heats it till it boils. The graph
Read the assertion and reason carefully to mark the
between temperature and time is as follows. Heat
correct option out of the options given below :
supplied to the wax per minute and boiling point
are respectively [BHU 1994] (a) If both assertion and reason are true and the
250
Temperature

reason is the correct explanation of the assertion.

200
(b) If both assertion and reason are true but reason is
(°C)

150
not the correct explanation of the assertion.
100 (c) If assertion is true but reason is false.
50 (d) If the assertion and reason both are false.
0 (e) If assertion is false but reason is true.
1 2 3 4 5 6 7 8
Time 1. Assertion : The melting point of ice decreases
(Minute) with increase of pressure.

(a) 500 cal, 50°C (b) 1000 cal, 100°C Reason : Ice contracts on melting. [AIIMS 2004]

(c) 1500 cal, 200°C (d) 200°C 2. Assertion : Fahrenheit is the smallest unit
12. The graph signifies [JIPMER 1999] measuring temperature.
Reason : Fahrenheit was the first temperature
Temperature

scale used for measuring

temperature.
[AIIMS 1999]
3. Assertion : Melting of solid causes no change in
Time internal energy.

(a) Adiabatic expansion of a gas Reason : Latent heat is the heat required to
melt a unit mass of solid. [AIIMS 1998]
(b) Isothermal expansion of a gas
4. Assertion : Specific heat capacity is the cause
(c) Change of state from liquid to solid of formation of land and sea breeze.

(d) Cooling of a heated solid Reason : The specific heat of water is more
than land.
13. Which of the substances A, B or C has the highest [AIIMS 1995]
specific heat ? The temperature vs time graph is
5. Assertion : A brass disc is just fitted in a hole
shown in a steel plate. The system must be
cooled to loosen the disc from the
A
hole.
Temperature

B
Reason : The coefficient of linear expansion
(T)

C for brass is greater than the

coefficient of linear expansion for
steel.
Time (t)
6. Assertion : The coefficient of volume expansion
–1
(a) A (b) B has dimension K .

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 Thermodynamics
Reason : The coefficient of volume expansion 6 d 7 c 8 a 9 b 10 b
is defined as the change in volume 11 c 12 c 13 c 14 c 15 c
per unit volume per unit change in
16 d 17 b 18 c 19 c 20 c
temperature.
21 c 22 a 23 d 24 a 25 c
7. Assertion : The temperature at which
26 a 27 b 28 a 29 c 30 c
Centigrade and Fahrenheit
thermometers read the same is – 31 a 32 d 33 a 34 d 35 a
40°.
Reason : There is no relation between Thermal Expansion
Fahrenheit and Centigrade
1 c 2 a 3 b 4 d 5 c
temperature.
6 c 7 c 8 c 9 b 10 c
8. Assertion : When a solid iron ball is heated,
percentage increase is its volume is 11 a 12 b 13 b 14 d 15 a
largest. 16 d 17 d 18 d 19 d 20 a
Reason : Coefficient of superficial expansion is 21 b 22 c 23 a 24 a 25 a
twice that of linear expansion where 26 b 27 c 28 d 29 a 30 d
as coefficient of volume expansion is
31 b 32 a 33 a 34 c
three time of linear expansion.
9. Assertion : A beaker is completely filled with Calorimetry
water at 4°C. It will overflow, both
when heated or cooled. 1 b 2 b 3 c 4 c 5 d

Reason : There is expansion of water below 6 a 7 c 8 a 9 d 10 a

and above 4°C. 11 b 12 c 13 a 14 c 15 b

10. Assertion : Latent heat of fusion of ice is 16 a 17 b 18 a 19 a 20 c

–1
336000 J kg . 21 b 22 b 23 a 24 d 25 a

Reason : Latent heat refers to change of state 26 a 27 b 28 a 29 d 30 b

without any change in temperature 31 a 32 b 33 b 34 a 35 a

11. Assertion : Two bodies at different 36 b 37 c 38 b 39 a 40 a

temperatures, if brought in thermal 41 a 42 b 43 d 44 b 45 c
contact do not necessary settle to the 46 c 47 a 48 b 49 b 50 a
mean temperature. 51 c 52 d 53 c 54 b 55 b
Reason : The two bodies may have different 56 a 57 d 58 d 59 d 60 b
thermal capacities.
61 c 62 a 63 a 64 a 65 a
12. Assertion : Specific heat of a body is always 66 c 67 a 68 a 69 a 70 a
greater than its thermal capacity.
71 b 72 d 73 c 74 a 75 d
Reason : Thermal capacity is the required for 76 b 77 c 78 b 79 d 80 c
raising temperature of unit mass of
81 b 82 d
the body through unit degree.
13. Assertion : Water kept in an open vessel will
quickly evaporate on the surface of Critical Thinking Questions
the moon.
1 c 2 a 3 d 4 c 5 b
Reason : The temperature at the surface of the
moon is much higher than boiling 6 a 7 bd 8 d 9 c 10 d
point of the water. 11 b 12 b 13 b 14 a 15 b
14. Assertion : The molecules at 0ºC ice and 0ºC 16 a 17 a 18 c 19 c 20 b
water will have same potential
21 a 22 c 23 d 24 c 25 c
energy.
26 b 27 a
Reason : Potential energy depends only on
temperature of the system.
Graphical Questions

1 b 2 c 3 a 4 a 5 d
6 b 7 a 8 a 9 a 10 bc
11 c 12 c 13 c 14 c

Thermometry Assertion and Reason

1 a 2 c 3 e 4 a 5 a
1 d 2 b 3 a 4 c 5 b

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 Thermodynamics
6 a 7 c 8 a 9 a 10 b 18. (c) Thermoelectric thermometer is used for
11 a 12 d 13 a 14 d finding rapidly varying temperature.
19. (c) Due to evaporation cooling is caused which
lowers the temperature of bulb wrapped in
wet hanky.
F  32 K  273 x  32 x  273
20. (c)    
9 5 9 5
x  574 .25

Thermometry C F  32 C (140  32 )
21. (c)     C  60 
5 9 5 9
1. (d) T  273 .15  tC  0  273 .15  tC C F  32 t t  32
22. (a)     t   40 
 t  273 .15 C 5 9 5 9
C F  32 183 F  32 23. (d) Standardisation of thermometers is done with
2. (b)     F  297 F
5 9 5 9 gas thermometer.

F  32 K  273 F  32 95  273 24. (a) For gases  is more.

3. (a)     F  288 F
9 5 9 5 25. (c) The boiling point of mercury is 400°C.
Therefore, the mercury thermometer can be
4. (c) Temperature change in Celsius scale =
used to measure the temperature upto 360°C.
Temperature change in Kelvin scale = 27 K
(Pt  P0 ) (60  50 )
5. (b) Change in resistance 3.70  2.71  0.99  26. (a) t   100 C   100  25 C
(P100  P0 ) (90  50 )
corresponds to interval of temperature 90°C.
27. (b) By filling nitrogen gas at high pressure, the
So change in resistance 3.26  2.71  0.55  boiling point of mercury is increased which
Corresponds to change in temperature extend the range upto 500°C.
90 28. (a) Pyrometer is used to measure very high
  0 .55  50 C
0 .99 temperature.
6. (d) – 200°C to 600°C can be measured by F  32 K  273 F  32 0  273
29. (c)   
platinum resistance thermometer. 9 5 9 5
7. (c) Pyrometer can measure temperature from  F  459 .4F  460 F
800°C to 6000°C. Hence temperature of sun is
measured with pyrometer.

8. (a) v 2  T
9. (b) Thermoelectric thermometer is based on
Seeback Effect.
10. (b) Maximum density of water is at 4°C
C F  32 4 F  32
Also     F  39 .2F
5 9 5 9
11. (c) Production and measurement of temperature
close to 0 K is done in cryogenics

12. (c)
13. (c) At absolute zero (i.e. 0 K) vrms becomes zero.
14. (c)
15. (c) We know that P  P0 (1  t) and V  V0 (1  t)

and   (1 / 273 ) / C for t  273 C , we have

P  0 and V  0
Hence, at absolute zero, the volume and
pressure of the gas become zero.
16. (d) Zero kelvin  273 C (absolute temperature).
As no matter can attain this temperature,
hence temperature can never be negative on
Kelvin scale.
C F  32 25 F  32
17. (b)     F  77 F .
5 9 5 9

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