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Physics · PYQ NEET UG 2016(1)
हिन्दीA refrigerator works between \( 4^\circ\text{C} \) and \( 30^\circ\text{C} \). It is required to remove 600 calories of heat every second in order to keep the temperature of the refrigerated space constant. The power required is [Take 1 cal = 4.2 joules]
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Correct answer · Option A
\( 236.5\text{ W} \)
Explanation
Temperatures: \( T_1 = 30 + 273 = 303\text{ K} \), \( T_2 = 4 + 273 = 277\text{ K} \). COP \( = \frac{T_2}{T_1 - T_2} = \frac{277}{303 - 277} = \frac{277}{26} \). Work per second \( W = \frac{Q_2}{\text{COP}} = \frac{600 \times 4.2}{277/26} \approx 236.5\text{ W} \).
