Question

A heat engine is supplied with 250 kJ/s of heat at a constant fixed temperature of ${227}^{0}C$; the heat is rejected at ${27}^{0}C$, the cycle is reversible, then what amount of heat is rejected?

• A. 24kJ/s
• B. 223kJ/s
• C. 150kJ/s
• D. none of the above

Answer 1

The correct option is C 150kJ/s

The temperature in kelvin scales are $T_1=273+27=300K,T_2=273+237=500K$

$T_1$is temperature of sink And$T_2$ is temperature of source hence by efficiency we get

$\eta =1-\frac{T_1}{T_2}=1-\frac{Q_1}{Q_2}$

$Q_1=\frac{T_1}{T_2}\ast Q_2=\frac{300}{500}\ast 250=150kW$