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MHT CET 2019 (2 May, Shift 1) · Heat Engines, Refrigerators & Second Law

Heat Engines, Refrigerators & Second Law question from MHT CET 2019 (2 May, Shift 1)

Q57MHT CET 2019 · 2 MAY · SHIFT 1Easy

Heat Engines, Refrigerators & Second Law

If $\alpha$ is the coefficient of performance of a refrigerator and ' $Q$ ' is heat released to the hot reservoir, then the heat extracted from the cold reservoir ' $Q_2$ ' is

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Answer: (c)

$\alpha = \frac{Q_2}{W} = \frac{Q_2}{Q_1 - Q_2}$
$\alpha Q_1 - \alpha Q_2 = Q_2 \Rightarrow Q_2 = \frac{\alpha Q_1}{1 + \alpha}$
So the answer is (c).

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