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A heat engine operates between a cold reservoir at temperature T 2 = 400   K and a hot reservoir at temperature T 1 . It takes 300   J of heat from the hot reservoir and delivers 240   J of heat to the cold reservoir in a cycle. The minimum temperature of the hot reservoir has to be

Correct answer

500

Step-by-step solution

Recall the formula of efficiency of heat engine in terms of work done and heat supplied to the source, η = W Q H = 1 - T L T H , here T L   &   T H , is the temperature of the sink and source ⇒ 60 300 = 1 - 400 T H ⇒ T H = 500   K .

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