Project ForgeThermodynamics
Entropy & Second Law
GATE 2020
Medium
If a reversed Carnot cycle operates between the temperature limits of 27°C and −3°C, then the ratio of the COP of a refrigerator to that of a heat pump (COP of refrigerator / COP of heat pump) based on the cycle is __________ (round off to 2 decimal places).
0.9(± 0.02 accepted)
Explanation
Th=300K, Tc=270K. COP_refrigerator=Tc/(Th−Tc)=270/30=9. COP_heat-pump=Th/(Th−Tc)=300/30=10. Ratio = 9/10 = 0.90.
Source: GATE ME 2020 Session 2 (ME-2) (2020)
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