250+ TOP MCQs on Carnot, Rankine and Reheat cycle – 1 and Answers

Steam and Gas Turbines Multiple Choice Questions on “Carnot, Rankine and Reheat cycle”.

1. Carnot engine follows ____________
a) Isothermal process
b) Isoentropic process
c) Isothermal and Isoentropic process
d) None of the mentioned
Answer: c
Clarification: Carnot cycle process follows 4 process. They are
Isothermal heat addition
Reversible adiabatic expansion
Reversible isothermal compression
Reversible adiabatic heat rejection.

2. Clausius inequality is applied at _____________
a) reversible isothermal heat addition
b) reversible adiabatic expansion
c) reversible isothermal compression
d) reversible isothermal heat rejection
Answer: c
Clarification: In reversible adiabatic compression entropy is same as from reversible isothermal heat addition and this can be found out by clausius inequality.

3. During reversible adiabatic explansion and compression entropy doesnot change.
a) True
b) False
Answer: a
Clarification: Adiabatic process mean there is no heat transfer and if there is no heat transfer entropy doesnot change.

4. What happens if all the process in carnot cycle be reversed?
a) Works as heat engine
b) PMM1 occurs
c) Works as refrigerator
d) PMM2 occurs
Answer: c
Clarification: When all the process in carnot cycle be reversed heat is absorbed from the body and reduces the temperature of the body which means a refrigerator. When carnot cycle is not reversed it acts as a heat engine.

5. Working fluid of rankine cycle usually _____________
a) Water
b) Methane
c) Hard water
d) None of the mentioned
Answer: a
Clarification: Water is used as working fluid in rankine cycle.

6. Steam turbines work on __________
a) Rankine cycle
b) Carnot cycle
c) Dual cycle
d) None of the mentioned
Answer: a
Clarification: Rankine cycle is generally used where heat energy is to be converted in mechanical energy.

7. In non ideal rankine cycle the compression of pump and expansion of turbine is isoentropic.
a) True
b) False
Answer: b
Clarification: In general isoentropic cases are harder to occur and hence in rankine cycle they doesnot exist as isoentropic process.

8. What is the use of reheat cycle in steam turbines?
a) To remove the moisture from the steam
b) To increase the steam temperature
c) To increase steam pressure
d) None of the mentioned
Answer: a
Clarification: Reheat cycle is worked with rankine cycle to remove the moisture from the steam.

9. In rankine cycle with reheat how mny turbines work?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: One turbine is to produce work and the other turbine is to reheat.

10. Reheat temperatures are very close to ______ temperature.
a) inlet
b) outlet
c) intermediate
d) none of the mentioned
Answer: a
Clarification: After passing from the first turbine again the steam enters the boiler to raise their temperature close to the inlet temperature and then enters the low pressure turbine.