Question
A Carnot refrigerator operates between 250K and 300K. Calculate its coefficient of performance.

Answer

Data: $T _{ C }=250 K _{,} T _{ H }=300 K$
$
K =\frac{T_{ C }}{T_{ H }-T_{ C }}=\frac{250 K }{300 K -250 K }=\frac{250}{50}=5
$
This is the coefficient of performance of the refrigerator.

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