A Carnot heat engine has an efficiency of $10 \%$. If the same engine is worked backward to obtain a…
A Carnot heat engine has an efficiency of $10 \%$. If the same engine is worked backward to obtain a refrigerator, then the coefficient of performance of the refrigerator is
8
9
5
6
Solution
For heat engine, $\eta_E=10 \%$
If same engine works as a refrigerator, then
$(\mathrm{COP})_R=\frac{1-\eta}{\eta}=\frac{1-0.1}{0.1}=9$