Question

Two carnot engines A and B are operated in series. The first one A receives heat at `900K` and rejects it to a reservoir at `T K`. The second engine B receives the heat rejected by the first engine and rejects it to a heat reservoir at `400K`. Calculate the value of `T`, when the efficiency ot two engines is the same.

Answer 1

Correct Answer - `600K`
Here, `eta=(1-T/(900))=(1-(400)/T)`
`:. T/(900)=(400)/T or T=sqrt(36xx10^(4))=600K`