Thermodynamics MCQ
SET-4
61. The hyperbolic process is governed by
- A. Boyle’s law
- B. Charles’ law
- C. Gay-Lussac law
- D. Avogadro’s law
Answer: A
62. A closed system is one in which heat and work crosses the boundary of the system but the mass of the working substance does not crosses the boundary of the system.
- A. Yes
- B. No
Answer: A
63. The entropy of water at 0°C is assumed to be
- A. 1
- B. 0
- C. -1
- D. 10
Answer: B
64. The greater the pressure difference in throttling, the lesser is the irreversibility.
- A. Yes
- B. No
Answer: B
65. During which of the following process does heat rejection takes place in Carnot cycle?
- A. Isothermal expansion
- B. Isentropic expansion
- C. Isothermal compression
- D. Isentropic compression
Answer: C
66. Which is the incorrect statement about Carnot cycle?
- A. It is used as the alternate standard of comparison of all heat engines.
- B. All the heat engines are based on Carnot cycle.
- C. It provides concept of maximising work output between the two temperature limits.
- D. all of the above
Answer: B
67. When two bodies are in thermal equilibrium with a third body, they are also in thermal equilibrium with each other. This statement is called
- A. Zeroth law of thermodynamics
- B. First law of thermodynamics
- C. Second law of thermodynamics
- D. Kelvin Planck’s law
Answer: A
68. The area under the temperature-entropy curve (T – s curve) of any thermodynamic process represents
- A. heat absorbed
- B. heat rejected
- C. either (a) or (b)
- D. none of these
Answer: C
69. The free expansion process is a constant enthalpy process.
- A. Correct
- B. Incorrect
Answer: A
70. The specific heat at constant volume is
- A. the amount of heat required to raise the temperature of unit mass of gas through one degree, at constant pressure
- B. the amount of heat required to raise the temperature of unit mass of gas through one degree, at constant volume
- C. the amount of heat required to raise the temperature of 1 kg of water through one degree
- D. any one of the above
Answer: B
71. One kg of carbon produces __________ kg of carbon dioxide.
- A. 3/7
- B. 7/3
- C. 11/3
- D. 3/11
Answer: C
72. Ericsson cycle consists of two constant pressure and two isothermal processes.
- A. Agree
- B. Disagree
Answer: A
73. The isothermal and isentropic processes are reversible non-flow processes.
- A. Agree
- B. Disagree
Answer: A
74. The blast furnace gas is a by-product in the production of pig iron in the blast furnace.
- A. Yes
- B. No
Answer: A
75. The heat supplied to the gaS at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2 – T1 = Rise in temperature, and R = Gas constant)
- A. mR(T2 – T1)
- B. mcv(T2 – T1)
- C. mcp(T2 – T1)
- D. mcp(T2 + T1)
Answer: B
76. Liquid fuels have lower efficiency than solid fuels.
- A. True
- B. False
Answer: B
77. The heat absorbed during a polytropic process is
78. Liquid fuels consist of hydrocarbons.
- A. True
- B. False
Answer: A
79. The expansion ratio (r) is the ratio of (where v1 = Volume at the beginning of expansion, and v2 = Volume at the end of expansion)
80. The dual combustion cycle consists of one constant pressure, two constant volume and two isentropic processes.
- A. Agree
- B. Disagree
Answer: A