393. Air refrigerators work on
A.Carnot cycle
B.Reversed joule cycle
C.Atkinson cycle
D.Stirling cycle

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394. Rankine cycle consists of
A.Four processes
B.Five processes
C.Six processes
D.Three processes

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395. Relative efficiency of a gas power cycle is given as the ratio of
A.Actual thermal efficiency to air standard efficiency
B.Theoretical thermal efficiency to air standard efficiency
C.Air standard efficiency to actual thermal efficiency
D.Brake thermal efficiency to air standard efficiency

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396. It is proposed to make a direct heat to work converter out of an elementary system which absorbs heat while doing isothermal work exactly equal to the heat absorbed, thereby keeping internal energy constant. Such a system is
A.Not possible
B.Possible
C.Not desirable
D.Commendable

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397. Maxwell's thermodynamic relations are applicable to
A.Reversible processes
B.Chemical system in equilibrium
C.Mechanical system in equilibrium
D.Thermodynamic processes

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398. Pick up the correct statement. An engine working between positive temperatures
A.Can be a heat pump
B.Can not be a heat pump
C.Must be a heat pump
D.Can be a heat pump only if friction less machine is used

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399. Thermal power plant works on
A.Carnot cycle
B.Joule cycle
C.Rankine cycle
D.Otto cycle

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