Assignment 10.2: During one cycle, an engine extracts 2.00 × 103 J of energy from the hot reservoir and transfers 1.5 × 103 J to a cold reservoir. (a) Find the thermal efficiency of the engine. (b) How much work this engine do in one cycle? (c) What average power does this engine generates if it goes through four cycles in 2.50 s?
Solution
Efficiency is the ratio of the work done and the heat given to the system.Now put values,
Work is equal to the difference of energy absorbed from the source and rejected to the sink. Therefore,
Power is the rate of work done, i-e, work done in one second. The engine goes through four cycles in 2.50 s and the work done in one cycle is calculated in part (b). Therefore, work in four cycles = 5.0 × 102 × 4 = 20.0 × 102 Now this work is done in 2.50 s, therefore,