## Class 11 Physics Objective Chapter – 11 Thermal Properties of Matter

Here we are providing NCERT Class 11 Physics Objective Chapter – 11 Thermal Properties of Matter Chapter Wise MCQs for board exam is very important for board exam preparation. This book explains all the concepts and topics in very simple language that the students can easily understand the complex subjects also. This NCERT Class 11 Physics MCQs Chapter – 11 Thermal Properties of Matter Chapter consist all important topic regarding NCERT Class 11 Physics Objective Chapter – 11 Thermal Properties of Matter. This book basically covers all the major and minor elements that together form a democratic government. Topics like power-sharing, federalism, democracy and diversity, political parties, consequences of democracy, challenges to democracy etc. have been discussed in the NCERT Class 11 Physics Objective Chapter – 11 Thermal Properties of Matter. The question papers in CBSE board exams are generally based on the latest NCERT books. Hence, students must follow the NCERT book to prepare effectively for their Class 11 Physics exam. If you want color notes then click here

## Class 11 Physics Objective Chapter – 11 Thermal Properties of Matter

1. Absorptive power of perfectly black body is

( a )  Zero

( b )  Infinity

( c )  One

( d )  Constant

Ans:- ( c)

2. A liquid with coefficient of cubical expansion γ is contained in a vessel having coefficient of linear expansion γ ⁄ 7. When heated, what will happen to the level of the liquid in the vessel?

( a )  It falls

( b )  It rises

( c )  Remains unchanged

( d )  It may rise or fall depending upon the nature of the container

Ans:- ( c)

3. The form of energy transferred between two systems or a system and its surrounding by virtue of temperature difference is called as

( a )  Heat

( b )  Temperature

( c )  Both a and b

( d )  None

Ans:- ( a)

4. S.I. unit of heat is

( a )  Joule

( b )  Calorie

( c )  Kilo calorie

( d )  None of the above

Ans:- ( a)

5.The reading of Centigrade thermometer coincides with that of Fahrenheit thermometer in a liquid. The temperature of the liquid is

( a )  40°C

( b )  100°C

( c )  313°C

( d )  0ºC

Ans:- ( a)

6.In order that the heat flows from one part of a solid to another part, what is required?

( a )  Uniform density

( d )  Uniform temperature

Ans:- ( b)

7. Which of the following will expand the most for same rise in temperature?

( a )  Aluminium

( b )  Wood

( c )  Glass

( d )  All will expand same

Ans:- ( a)

8. Two stars A and B radiate maximum energy at 3600°A and 4800°A respectively. Then the ratio of absolute temperatures of A and B is

( a )  256 : 81

( b )  81 : 256

( c )  3 : 4

( d )  4 : 3

Ans:- ( d)

9.A black body at hot temperature at 227°C radiates heat at a rate of 5 cal/cm²s. at a temperature of 727°C the rate of heat radiated per unit area will be

( a )  50 cal/cm²s

( b )  250 cal/cm²s

( c )  80 cal/cm²s

( d )  100 cal/cm²s

Ans:- ( c)

10. The temperature determines the direction of net change of:

( a )  gross potential energy

( b )  intermolecuiar potential energy

( c )  gross kinetic energy

( d )  intermolecuiar kinetic energy

Ans:- ( d)

11. The SI unit of heat energy is

( a )  J

( b )  N

( c )  Pa

( d )  N/m2

Ans:- ( a)

12. Which of the following will radiate heat to large extent?

( a  )  Rough surface

( b  )  Polished surface

( c  )  Black rough surface

( d  )  Black polished surface

Ans:- ( c)

13. Expansion during heating

( a )  generally decreases the density of a material

( b )  None of these

( c )  increases the weight of a material

( d )  occurs only in solids

Ans:- ( a)

14.The sprinkling of water slightly reduces the temperature of a closed room because

( a )  temperature of water is less than that of the room

( b )  specific heat of water is high

( c )  water has large latent heat of vaporisation

( d )  water is a bad conductor of heat

Ans:- ( c)

15. An iron tyre is to be fitted on to a wooden wheel 1m in diameter. The diameter of tyre is 6 mm smaller than that of wheel. The tyre should be heated so that its temperature increases by a minimum of (  the coefficient of cubical expansion of iron is 3.6 × 10-5/°C )

( a ) 500°C

( b ) 334°C

( c ) 1000°C

( d ) 167°C

Ans:- ( a)

16. Two spheres made of same material have radii in the ratio 2 : 1. if both the spheres are at same temperature, then what is the ratio of heat radiation energy emitted per second by them?

( a )  1 : 4

( b )  4 : 1

( c )  3 : 4

( d )  4 : 3

Ans:- ( b)

17. A body cools from 50°C to 46°C in 5 minutes and to 40°C in the next 10 minutes. The surrounding temperature is

( a ) 30°C

( b ) 28°C

( c ) 36°C

( d ) 32°C

Ans:- ( a)

18. Thermal equilibrium implies equality of:

( a )  energy

( b )  internal energy

( c )  K.E.

( d )  temperature

Ans:- ( d)

19. The SI unit of temperature is

( a )  Kelvin

( b )  Degree Celsius

( c )  Degree Fahrenheit

( d )  All

Ans:- ( a)

20. Co-efficient of reflection, coefficient of absorption and coefficient transmission are related as

( a  )  a + r + 1 = 1

( b  )  a + r + t1 1

( c  )  a + r = -t

( d  )  a1 r + 1

Ans:- ( a)

21. Which of the following will expand the most for same rise in temperature?

( a )  Aluminium

( b )  Wood

( c )  Glass

( d )  All will expand same

Ans:- ( a)

22. Which of the following is not close to a black body?

( a )  Black board paint

( b )  Green leaves

( c )  Black holes

( d )  Red roses

Ans:- ( a)

23. The triple point of a substance is unique i.e. it occurs at one particular set of values of pressure and temperature

( a )  Assertion is correct, reason is correct; reason is a correct explanation for assertion

( b )  Assertion is incorrect, reason is correct

( c )  Assertion is correct, reason is correct; reason is not a correct explanation for assertion

( d )  None of these

Ans:- ( a)

24. The earth intercepts approximately one billionth of the power radiated by the sun. if the surface temperature of the sun were to drop by a factor of 2, the average radiant energy incident on earth per second would reduce by factor of

( a ) 2

( b ) 4

( c ) 8

( d ) 16

Ans:- ( d)

25.For which of the following process, the thermal conduction is maximum?

( a )  Combustion

( c )  Convection

( d )  Conduction

Ans:- ( b)

26. Two bars of copper having same length but an equal diameter are heated to the same temperature. The change in length will be:

( a )  more in thicker bar

( b )  more in thinner bar

( c )  same for both

( d )  determined by the ratio of length and diameter of the bars

Ans:- ( c)

27. The commonly used unit of temperature is

( a )  Kelvin

( b )  Degree Fahrenheit

( c )  Degree Celsius

( d )  All

Ans:- ( c)

28. The good absorber of heat are

( a  )  Non-emitter

( b  )  Poor-emitter

( c  )  Good-emitter

( d  )  Highly polished

Ans:- ( c)

29.A metal sheet with a circular hole is heated. The hole

( a )  gets larger

( b )  gets deformed

( c )  gets smaller

( d )  None of these

Ans:- ( a)

30.According to Newton’s law of cooling, the rate of cooling of a body is proportional to ( Dq)n, where Dq is the difference of the temperature of the body and the surroundings, and n is equal to

( a )  two

( b )  three

( c )  four

( d )  one

Ans:- ( d)

31. A metal sheet with a circular hole is heated. The hole

( a )  gets larger

( b )  gets deformed

( c )  gets smaller

( d )  None of these

Ans:- ( a)

32. A bucket full of hot water is kept in a room and it cools from 75°C to 70°C in t1 minutes from 70°C to 65°C in t2 minutes and from 65°C to 60°C in t3 minutes; then

( a )  t1 – t2 = t3

( b )  t1 < t2 < t3

( c )  t1 > t2 > t3

( d )  t1 < t> t3

Ans:- ( b)

33. Two stars A and B radiate maximum energy at 3600°A and 4800°A respectively. Then the ratio of absolute temperatures of A and B is

( a )  256 : 81

( b )  81 : 256

( c )  3 : 4

( d )  4 : 3

Ans:- ( d)

34.A metallic ball has a spherical cavity at its centre. If the ball is heated, what happens to the cavity?

( a )  Its volume decreases

( b )  Its volume increases

( c )  Its volume remains unchanged

( d )  Its volume may increase or decrease depending upon the nature of the metal

Ans:- ( b)

35.Charle’s law is given by

( a )  V = constant

( b )  V/T = constant

( c )  T = constant

( d )  None

Ans:- ( b)

36.Expansion during heating

( a  )  generally decreases the density of a material

( b  )  None of these

( c  )  increases the weight of a material

( d  )  occurs only in solids

Ans:- ( a)

37.A solid ball of metal has a spherical cavity inside it. The balln is heated. The volume of cavity will

( a )  increase

( b )  decrease

( c )  remain unchanged

( d )  have its shape changed

Ans:- ( a)

38. metallic rod l cm long, A square cm in cross-section is heated through tºC. If Young’s modulus of elasticity of the metal is E and the mean coefficient of linear expansion is a per degree celsius, then the compressional force required to prevent the rod from expandin

( a )  E A ∝ t

( b )  E A ∝ t/( 1 + at)

( c )  E A ∝ t/( 1 – ∝ t)

( d )  E l ∝ t

Ans:- ( a)

39. A solid ball of metal has a spherical cavity inside it. The balln is heated. The volume of cavity will

( a )  increase

( b )  decrease

( c )  remain unchanged

( d )  have its shape changed

Ans:- ( a)

40. A sphere, a cube and a thin circular plate, all made of the same material and having the same mass are initially heated to a temperature of 3000°K, which of these will cool fastest?

( a )  Sphere

( b )  Cube

( c )  Plate

( d )  None

Ans:- ( c)

41. Unit of Stefans constant is given by

( a )  W/ m K²

( b )  W/ m² K²

( c )  W²/ m² K4

( d )  W/ mK

Ans:- ( b)

42. Gas thermometers are more sensitive than liquid thermometers as the gases

( a )  have low specific heat

( b )  have high specific heat

( c )  have large coefficient of expansion

( d )  are lighter

Ans:- ( c)

43. The absolute zero temperature is given by

( a )  +273.15°C

( b )  -273.15°C

( c )  0°C

( d )  1°C

Ans:- ( b)

44. A circular disc is heated. Its M.I. about an axis passing through its centre and perpendicular to its plane

( a  )  increases

( b  )  decreases

( c  )  remains same

( d  )  first increases and then decreases

Ans:- ( a)

45. Water kept in an open vessel will quickly evaporate onthe surface of the moon.

Reason : The temperature at the surface of the moon is much higher than boiling point of the water.

( a )  Assertion is correct, reason is incorrect

( b )  None of these

( c )  Assertion is correct, reason is correct; reason is not a correct explanation for assertion

( d )  Assertion is correct, reason is correct; reason is a correct explanation for assertion

Ans:- ( a)

46. A black body rediates energy at the rate of E watt per metre2 at a high temperature T K. when the temperature is reduced to ( T/2 )  K, the radiant energy will be

( a )  E/16

( b )  E/4

( c )  E/2

( d )  2E

Ans:- ( a)

47. The process of heat transfer in which heat is transferred with actual migration of medium particles is known as ( AFMC- 94)

( a )  Conduction

( b )  Convection

( d )  Reflection

Ans:- ( b)

48. Which of the following statement is wrong?

( a )  Rough surfaces are better radiators tan smooth surfaces

( b )  Highly polished mirror surfaces are very good radiators

( c )  Black surfaces are better absorbers then white ones

( d )  Black surfaces are better radiators then white ones

Ans:- ( b)

49. A metal piece heated to T1°K. The temperature of the surrounding is T2°K. the heat in the surrounding due to radiation is proportional to

( a )  ( T14 – T24)

( b )  ( T1 – T2)4

( c )  ( T14 + T24)

( d )  ( T13 – T23)

Ans:- ( a)

50. An iron ball is heated. The percentage increase will be largest in

( a )  density

( b )  surface area

( c )  diameter

( d )  volume

Ans:- ( d)

51.The increase in dimensions of body due to the increase in temperature of the body is called as

( a )  Thermal expansion

( b )  Linear expansion

( c )  Area expansion

( d )  Volume expansion

Ans:- ( a)

52. In which process the rate of transfer of heat is maximum?

( a  )  Conduction

( b  )  Convection

( d  )  In all these heat is transferred with the same velocity

Ans:- ( c)

53. Two marks on a glass rod 10 cm apart are found to increase their distance by 0.08 mm when the rod is heated from 0°C to 100°C. A flask made of the same glass as that of rod measures a volume of 1000 cc at 0°C. The volume it measures at 100°C in cc is

( a )  1002.4

( b )  1008.2

( c )  1004.2

( d )  1006.4

Ans:- ( a)