engineering recuitment BPSC AE Mock Test 2025 Thermodynamics Second Law of Thermodynamics and Entropy
Two reversible engines are connected in series between a heat source and a sink. The efficiencies of these engines are 60% and 50% respectively. If these two engines are replaced by a single reversible engine, the efficiency of this engine will be
1
60%
2
70%
3
80%
4
90%