The thermal efficiency of a reversible heat engine operating between
two given thermal reservoirs is 0.4. The device is used either as a
refrigerator or as a heat pump between the same reservoirs. Then the
coefficient of performance as a refrigerator (COP)R and the co-efficient of
performance as a heat pump (COP)HP are
(A) (COP)R = (COP)HP = 0.6
(B) (COP)R = 2.5; (COP)HP = 1.5
(C) (COP)R = 1.5; (COP)HP = 2.5
(D) (COP)R = (COP)HP = 2.5

1 Answer

Answer :

(C) (COP)R = 1.5; (COP)HP = 2.5

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