Circle the correct statement(s) associated with isentropic efficiency. (a) Isentropic efficiency describes the thermal efficiency of heat engine in converting thermal energy to mechanical work. An isentropic efficiency of 90% indicates that the heat engine can convert 90%of thermal energy received from hot thermal reservoir to mechanical work. (b) Isentropic efficiency is a function of temperature of hot and cool thermal reservoir. (c) The isentropic efficiency of a reversible cycle is 100%, which does not violate the Kelvin-Planck statement of the 2nd Law. (d) Isentropic efficiency is defined as a parameter indicating the extent of excellence of an actual process when compared to isentropic process. An isentropic efficiency 90% of a heat engine indicates that work produced by this heat engine is 90% of that of an isentropic engine operated with the same two thermal reservoirs and the consumption of the same amount of thermal energy. (e) Isentropic efficiency indicates the extent of irreversibility involved in an actual cycle. The higher the isentropic efficiency, the less the irreversibility.

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