281. Which of the following parameters is constant for a mole for most of the gases at a given temperature and pressure
A.Enthalpy
B.Volume
C.Mass
D.Entropy

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282. Which of the following quantities do not represent the property of the system
A.Fpdv
B.Cyclic fpdv
C.Cyclic fvdp
D.None of the above

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283. Which is true for reversible polytropic process
A.Temperature remains constant
B.Some heat transfer takes place
C.Internal energy remains constant
D.Enthalpy remains constant

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284. Specific heat of air at constant volume Cv is equal to
A.0.17
B.0.21
C.0.24
D.1

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285. The value of Cv for oxygen is 5 cal/mole °K and the ratio of specific heats is 1.4. The difference between Cp and Cv is
A.1.4
B.2
C.2.4
D.3.2

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286. The value of polytropic exponent 'n' in the reversible polytropic process usually varies between
A.0.1 to 1
B.1 to 1.2
C.1.2 to 1.4
D.1.5 to 2.0

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287. If the value of 'n' is high in the polytropic process, then the compressor work between given pressure limits will be
A.Less
B.More
C.No effect
D.Zero

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