26. Joule’s law state that change of internal energy of a perfect gas is directly proportional to the change of temperature. (Yes/No)

Yes

27. Charles’ law states that all perfect gases change in volume by…………… of its original volume at 0C for every 1C change in temperature when pressure remains constant.

i) 1/27th ii) 1/93th iii) 1/173th iv) 1/273th

28. The general gas equation is pv = mRT where p = pressure, v = volume , T = Absolute temperature, and R = Gas constant. (True / False )

True

29. According to Avogadro’s law, the density of any two gases is …………….. their molecular masses it the gases are at the same temperature and pressure.

1. i) equal to
2. ii) directly proportional to
3. iii) inversely proportional to

30. Universal gas constant (or molar constant) of a gas is the product of molecular mass of the gas and the gas constant. R_u = M R

Where M= Molar Mass & R = Gas constant

True

31. The amount of heat required to raise the temperature of unit mass of a gas through one degree at constant pressure is called specific heat at constant pressure (yes/no)

Yes

32. The amount of heat required to raise the temperature of unit mass of a gas through one degree at constant volume is called specific heat at constant volume. (Yes/No)

Yes

33. The value of specific heat at constant pressure (C_p = 1.005) is ………… that of at constant volume (C_v = 0.717).

i) less than ii) equal to iii) More than

34. The amount of heat required to raise the temperature of 1000g water through one degree is called Kilojoule. (True/False)

True

35. The sum of internal energy (U) and the product of pressure and volume (p.v) is known as …..

1. i) work done
2. ii) entropy
3. iii) enthalpy
4. iv) non of the above

36. According to Regnault’s law, the specific heat at constant pressure (C_p) and specific heat at constant volume (C_v ) doesn’t change with the change in pressure and the temperature of the gas. (True/False)

True

37. When a system changes its state form one equilibrium state to another equilibrium state, then path of successive sates through which the system has passed, is known as

1. i) thermodynamic law
2. ii) thermodynamic system
3. iii) thermodynamic cycle
4. iv) None of these

38. The heat energy stored in the gas and used for raising the temperature of the gas is known as

1. i) external energy
2. ii) internal energy
3. iii) kinetic energy
4. iv) molecular energy

39. When gas is heated at constant pressure, the heat supplied is utilised in

1. i) increasing the internal energy of the gas
2. ii) doing some external work
3. iii) increasing the internal energy of gas and also for doing some external work
4. iv) none of the above

40. A process, in which the temperature of the working substance remains constant during expansion or compression, is called

1. a) isothermal process
2. b) hyperbolic process
3. c) adiabatic process
4. d) polytropic process

41. A process, in which the gas is heated or expanded in such a way that product of its pressure and volume remains constant, is called isothermal process (Yes/No)

No (is called Hyperbolic Process)

42. A process, in which the working substance neither receives nor gives out heat to its surroundings during its expansion or compression, is called

1. i) isothermal process
2. ii) hyperbolic process
3. iii) adiabatic process or isentropic process
4. iv) polytropic process

43. The free expansion process is a constant enthalpy process. (Correct/Incorrect)

Correct

44. The work done in a free expansion process is zero (True/False)

True

45. The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as

1. a) enthalpy
2. b) internal energy
3. c) entropy
4. d) external energy

46. The entropy of water at 0 ^.C is assumed to be

1. i) 1 ii) 0 iii) -1 iv) 10

47. The increase in entropy of a system represents

1. a) increase in the availability of energy
2. b) increase in temperature
3. c) decrease in pressure
4. d) degradation energy

48. A series of operations, which takes place in a certain order and restore the initial conditions at the end, is known as

1. a) reversible cycle
2. b) irreversible cycle
3. c) thermodynamic cycle
4. d) none of these

49. The main cause for the irreversibility is

1. a) mechanical and fluid friction
2. b) unrestricted expansion
3. c) heat transfer with a finite temperature difference
4. d) all of the above

50. The throttling process is …………. process.

1. a) reversible b)irreversible c) reversible or irreversible