Top 250+ Solved Engineering Thermodynamics MCQ Questions Answer
Q. Choose the correct statement
a. a) pressure, temp. &entropy are extensive properties
b. b) pressure, temp. &entropy are intensive properties
c. c) pressure, volume & temp. are extensive properties
d. d) volume & entropy are extensive properties
Q. The first law of thermodynamics defines
a. a) entropy
b. b) internal energy
c. c) work
d. d) heat
Q. A process becomes irreversible due to
a. a) work performed by thesystem
b. b) work performed uponthe system
c. c) heat supplied to the system
d. d) friction in the system
Q. What is the effect of reheat pressure on mean temperature of heat addition Tml?
a. reheat pressure is directly proportional to tml
b. reheat pressure is inversely proportional to tml
c. reheat pressure is equal to tml
d. tml is independent of reheat pressure
Q. Which of the following problems are posed by increasing the number of reheats?
a. cost & fabrication problems arise
b. heat transfer problems arise
c. frictional losses arise
d. none of the mentioned
Q. What is the most preferable dryness fraction of the exhaust steam?
a. 0.99
b. 0.77
c. 0.66
d. 0.88
Q. Which of the following represents the specific volume during phase transition.
a. vf-vg
b. vg-vf
c. vf+vg
d. none of the mentioned
Q. An 80 litre vessel contains 4 kg of R-134a at a pressure of 160 kPa. Determine the volume occupied by the vapour phase.
a. 0.0775 m3
b. 0.0575 m3
c. 0.0975 m3
d. 0.0375 m3
Q. Rankine cycle comprises of
a. two isentropic processes and two constant volume processes
b. two isentropic processes and two constant pressure processes
c. two isothermal processes and two constant pressure processes
d. none of the mentioned
Q. In Rankine cycle, the work output from the turbine is given by
a. change of internal energy between inlet and outlet
b. change of enthalpy between inlet and outlet
c. change of entropy between inlet and outlet
d. change of temperature between inlet and outlet
Q. Which of the following contributes to the improvement of efficiency of Rankine cycle in a Thermal Power Plant?
a. reheating of steam at intermediate stage
b. regeneration use of steam for heating boiler feed water
c. use of high pressures
d. all of the mentioned
Q. The temperature of feedwater leaving a heater is the saturation temperature at steam extraction pressure.
a. less than
b. equal to
c. more than
d. none of the mentioned
Q. The following also gave two-constant equations of state.
a. berthelot
b. dieterici
c. redlich-kwong
d. all of the mentioned