Q85 / 90 · JEE Main 2022 (26 Jun Shift 2) · Physics

A heat engine operates with the cold reservoir at temperature $324 K$ . The minimum temperature of the hot reservoir, if the heat engine takes $300 J$ heat from the hot reservoir and delivers $180 J$ heat to the cold reservoir per cycle, is _____ $K$ .

Correct answer: 540

Solution

Using the relation, $\frac{Q_{2}}{Q_{1}} = \frac{T_{2}}{T_{1}}$

Or $\frac{180}{300} = \frac{324}{T_{1}} \Rightarrow T_{1} = \frac{324 \times 300}{180} = 540 K$

Hence, the correct answer is 540.