JEE Main - Heat, temperature and thermal expansion Question Bank with Options

1. If a substance has a negative coefficient of thermal expansion, it means that its volume:

A) Increases when heated

B) Decreases when heated

C) Remains constant when heated

D) Expands linearly with temperature

2. Which of the following is a consequence of the anomalous expansion of water?

A) Lakes freeze from the top down

B) Lakes freeze from the bottom up

C) Ice floats on water

D) Water expands upon freezing

3. A bimetallic strip is made of two metals with different coefficients of thermal expansion. When heated, the strip bends towards the metal with the:

A) Higher coefficient of expansion

B) Lower coefficient of expansion

C) Equal coefficient of expansion

D) Zero coefficient of expansion

4. What is the coefficient of linear expansion of an ideal gas at constant pressure?

A) Zero

B) 1/T

C) 1/P

D) Constant

5. Which statement about heat and temperature is correct?

A) Temperature is the total kinetic energy, heat is the average kinetic energy.

B) Heat is transferred from higher temperature to lower temperature.

C) A hot object has more heat than a cold object.

D) Temperature determines the direction of heat flow.

6. The SI unit of heat is:

A) Calorie

B) Kilocalorie

C) Joule

D) British Thermal Unit

7. A brass scale measures 1m length correctly at 20°C. What length will it measure at 40°C for a true length of 1m?

A) Slightly more than 1m

B) Slightly less than 1m

C) Exactly 1m

D) Cannot be determined

8. Thermal expansion in solids is primarily due to:

A) Increased atomic spacing

B) Increased atomic vibration amplitude

C) Decreased atomic vibration amplitude

D) Decreased atomic spacing

9. Which of the following is a measure of the hotness or coldness of an object?

A) Heat

B) Internal energy

C) Temperature

D) Enthalpy

10. The volume expansion coefficient of a solid is approximately how many times its linear expansion coefficient?

A) 1

B) 2

C) 3

D) 4

11. If the length of a rod increases by 0.5% when heated by 10°C, the coefficient of linear expansion is:

A) 5 x 10⁻⁵ /°C

B) 5 x 10⁻⁴ /°C

C) 5 x 10⁻³ /°C

D) 0.5 x 10⁻⁴ /°C

12. A solid bar expands by 0.1% when its temperature is raised by 10°C. The coefficient of linear expansion is:

A) 10⁻⁴ /°C

B) 10⁻⁵ /°C

C) 10⁻³ /°C

D) 10⁻² /°C

13. Which property of matter is directly related to the average kinetic energy of its constituent particles?

A) Heat

B) Temperature

C) Pressure

D) Volume

14. The heat capacity of an object is:

A) The amount of heat needed to raise its temperature by 1°C

B) The amount of heat needed to raise the temperature of 1 kg of the substance by 1°C

C) The amount of heat needed to change its state

D) The rate of heat transfer

15. What is the Celsius temperature of absolute zero?

A) 0°C

B) -100°C

C) -273.15°C

D) -459.67°C

16. Why is glass less suitable than metal for making thermometers that measure very high temperatures?

A) Glass has a lower melting point

B) Glass has a higher coefficient of thermal expansion than mercury

C) Glass has a lower coefficient of thermal expansion than mercury

D) Glass is a better conductor of heat

17. A steel tape measure is more accurate at higher temperatures if it is calibrated at:

A) A lower temperature

B) A higher temperature

C) Room temperature

D) Absolute zero

18. The change in volume (ΔV) due to thermal expansion of a liquid is given by:

A) ΔV = V₀ / (γΔT)

B) ΔV = γV₀ΔT

C) ΔV = V₀ + γΔT

D) ΔV = γΔT / V₀

19. What is the temperature at which a solid melts into a liquid called?

A) Boiling point

B) Freezing point

C) Melting point

D) Critical point

20. A mercury thermometer works on the principle of:

A) Thermal conductivity

B) Thermal expansion of mercury

C) Thermal radiation

D) Specific heat capacity

21. Thermal expansion is a macroscopic manifestation of:

A) Intermolecular forces

B) Intermolecular vibrations

C) Intermolecular attraction

D) Intermolecular repulsion

22. Which of the following has the highest specific heat capacity?

A) Iron

B) Water

C) Aluminum

D) Copper

23. Specific heat capacity is defined as the heat required to raise the temperature of how much mass of a substance by 1°C?

A) 1 gram

B) 1 kg

C) 1 mole

D) Unit mass

24. The heat required to raise the temperature of 1 kg of a substance by 1°C is called its:

A) Specific heat capacity

B) Latent heat

C) Thermal conductivity

D) Heat capacity

25. If a solid has a coefficient of linear expansion α, its coefficient of superficial expansion is approximately:

A) α/2

B) α

C) 2α

D) 3α

26. What is absolute zero temperature in Fahrenheit?

A) -273.15°F

B) -459.67°F

C) 0°F

D) 32°F

27. A bimetallic strip bends with heating because:

A) Both metals expand equally

B) One metal expands more than the other

C) Both metals contract equally

D) One metal contracts more than the other

28. The coefficient of cubical expansion for a liquid is generally:

A) Equal to its coefficient of linear expansion

B) Twice its coefficient of linear expansion

C) Three times its coefficient of linear expansion

D) Independent of its coefficient of linear expansion

29. Which phenomenon is responsible for the apparent bending of a ruler when heated unevenly?

A) Thermal conduction

B) Thermal convection

C) Thermal expansion

D) Thermal radiation

30. What happens to the density of most substances when heated?

A) It increases

B) It decreases

C) It remains constant

D) It becomes zero

31. A metal rod of length 1m expands by 1mm when heated by 100°C. What is its coefficient of linear expansion?

A) 10⁻⁵ /°C

B) 10⁻⁶ /°C

C) 10⁻⁴ /°C

D) 10⁻³ /°C

32. Which of the following materials has the highest coefficient of linear expansion?

A) Steel

B) Aluminum

C) Glass

D) Brass

33. The anomalous expansion of water occurs between which temperatures?

A) 0°C and 100°C

B) 0°C and 4°C

C) 4°C and 100°C

D) 0°C and -10°C

34. When water is cooled from 4°C to 0°C, it:

A) Contracts

B) Expands

C) First expands then contracts

D) Its volume remains constant

35. Why are gaps left in railway tracks and bridges?

A) To reduce friction

B) To allow for thermal expansion

C) To improve aesthetics

D) To facilitate drainage

36. What is the coefficient of volume expansion (β) for an isotropic solid?

A) β = α

B) β = 2α

C) β = 3α

D) β = α/3

37. The coefficient of linear expansion (α) relates the change in length (ΔL) to the original length (L₀) and the change in temperature (ΔT) by the formula:

A) ΔL = L₀ / (αΔT)

B) ΔL = αΔT / L₀

C) ΔL = αL₀ΔT

D) ΔL = L₀ + αΔT

38. Which state of matter generally exhibits the most significant thermal expansion?

A) Solid

B) Liquid

C) Gas

D) Plasma

39. What is thermal expansion?

A) The change in temperature of a substance

B) The change in volume of a substance due to a change in temperature

C) The transfer of heat without a change in temperature

D) The process of a substance becoming a gas

40. When heat is added to a substance, what generally happens to its temperature?

A) It decreases

B) It remains the same

C) It increases

D) It depends on the pressure

41. Which of the following is a unit of heat energy?

A) Watt

B) Joule

C) Pascal

D) Newton

42. What is the relationship between heat and temperature?

A) Heat is a measure of temperature, while temperature is the transfer of energy.

B) Heat is the transfer of thermal energy, while temperature is a measure of the average kinetic energy of particles.

C) Temperature is the total energy of a system, while heat is the average energy.

D) Heat and temperature are identical concepts.

43. If the temperature of a room is 25°C, what is its equivalent temperature in Kelvin?

A) 25 K

B) 298.15 K

C) 248.15 K

D) 300 K

44. The conversion formula from Celsius (C) to Fahrenheit (F) is:

A) F = (9/5)C + 32

B) F = (5/9)C - 32

C) C = (9/5)F + 32

D) C = (5/9)F - 32

45. Which temperature scale is commonly used in scientific research and calculations?

A) Celsius

B) Fahrenheit

C) Kelvin

D) Rankine

46. What is the boiling point of water on the Fahrenheit scale?

A) 100°F

B) 32°F

C) 212°F

D) 0°F

47. What is the freezing point of water on the Celsius scale?

A) 0°C

B) 100°C

C) 32°F

D) -273.15°C

48. Which temperature scale has absolute zero as its lowest point?

A) Celsius

B) Fahrenheit

C) Kelvin

D) Réaumur

49. What does temperature measure at a microscopic level?

A) The total kinetic energy of the particles

B) The average kinetic energy of the particles

C) The potential energy of the particles

D) The vibrational frequency of the particles

50. Which of the following is the SI unit of temperature?

A) Celsius

B) Fahrenheit

C) Kelvin

D) Rankine

Heat, temperature and thermal expansion - Question Bank