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AP EAMCET202119 Aug 2021Evening ShiftPhysicsThermodynamicsActual

A refrigerator with coefficient of performance 0 . 25 releases 250 J of heat to a hot reservoir. The work done on the working substance is

Options

  1. A100 3 J
  2. B150 J
  3. C200 J
  4. D50 J

Correct answer

C. 200 J

Step-by-step solution

Given, Coefficient of performance, Q 2 W = 0 . 25 = 1 4 ⇒ Q 2 = W 4 Q 1 = Q 2 + W ⇒ Q 1 = W 4 + W ⇒ W = 250 4 5 = 200   J

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