Medium MCQ +4 / -1 PYQ · JEE Mains 2022

A Carnot engine takes 5000 kcal of heat from a reservoir at 727$^\circ$C and gives heat to a sink at 127$^\circ$C. The work done by the engine is

  1. A 3 $\times$ 10<sup>6</sup> J
  2. B Zero
  3. C 12.6 $\times$ 10<sup>6</sup> J Correct answer
  4. D 8.4 $\times$ 10<sup>6</sup> J

Solution

<p>Efficiency $\eta = 1 - {{{T_L}} \over {{T_H}}}$</p> <p>$= 1 - {{400} \over {1000}} = 0.6$</p> <p>$\Rightarrow 0.6 = {W \over Q}$</p> <p>$\Rightarrow W = 0.6Q = 3000$ kcal $=12.6 \times {10^6}$ J</p>

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law

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