A Carnot engine of efficiency 40 % , takes heat from a source maintained at a temperature of 500 K . It is desired to have an engine of efficiency 60 % . Then, the source temperature for the same sink temperature must be

Step-by-step solution

The formula for the efficiency of Carnot engine Working between temperature limits T 1   and   T 2 . T 1 > T 2 η = 1 - T 2 T 1 × 100 For η = 40   % ,   T 1 = 500   K 40 = 1 - T 2 500 × 100 T 2 = 300   K For η = 60   % , T 2 = 300   K (the source temperature of Carnot engine for the same sink temp), ⇒     60 = 1 - 300 T 1 × 100 ⇒   T 1 = 750   K