Q94 / 180 · AIIMS 2019 (25 May) · Physics

For a refrigerator, heat absorbed from source is $800 \mathrm{~J}$ and heat supplied to sink is $500 \mathrm{~J}$. Then find the coefficient of performance

A
$5 / 8$
B
$8 / 5$
Correct answer
C
$5 / 3$
D
$3 / 5$

Solution

Coefficient of performance $\alpha=\frac{Q_2}{Q_1-Q_2}=\frac{500}{800-500}=\frac{5}{3}$

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

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