Q139 / 160 · AP EAMCET 2024 (19 May Shift 2) · Physics

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

A
8
Correct answer
B
9
C
5
D
6

Solution

For heat engine, $\eta_E=10 \%$ If same engine works as a refrigerator, then $(\mathrm{COP})_R=\frac{1-\eta}{\eta}=\frac{1-0.1}{0.1}=9$

Hence, the correct answer is option: 'B'.

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