Suppose that two heat engines are connected i | vedclass

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(C) Let $Q_h$ be the heat absorbed by the first engine and $Q_m$ be the heat rejected by the first engine,which is absorbed by the second engine. Let

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$\epsilon_{net}=\epsilon_1+ \epsilon_2 - \epsilon_1 \epsilon_2$

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(C) Let $Q_h$ be the heat absorbed by the first engine and $Q_m$ be the heat rejected by the first engine,which is absorbed by the second engine. Let $Q_c$ be the heat rejected by the second engine.Efficiency of the first engine is $\epsilon_1 = \frac{W_1}{Q_h} \implies W_1 = \epsilon_1 Q_h$. The heat rejected is $Q_m = Q_h - W_1 = Q_h(1 - \epsilon_1)$.Efficiency of the second engine is $\epsilon_2 = \frac{W_2}{Q_m} \implies W_2 = \epsilon_2 Q_m = \epsilon_2 Q_h(1 - \epsilon_1)$.The total work done is $W_{net} = W_1 + W_2 = \epsilon_1 Q_h + \epsilon_2 Q_h(1 - \epsilon_1) = Q_h(\epsilon_1 + \epsilon_2 - \epsilon_1 \epsilon_2)$.The net efficiency is $\epsilon_{net} = \frac{W_{net}}{Q_h} = \frac{Q_h(\epsilon_1 + \epsilon_2 - \epsilon_1 \epsilon_2)}{Q_h} = \epsilon_1 + \epsilon_2 - \epsilon_1 \epsilon_2$.

List-$I$	List-$II$
$A$. $T_1 = 500 \text{ K}, T_2 = 300 \text{ K}$	$i$. $0.2$
$B$. $T_1 = 500 \text{ K}, T_2 = 350 \text{ K}$	$ii$. $0.3$
$C$. $T_1 = 800 \text{ K}, T_2 = 400 \text{ K}$	$iii$. $0.4$
$D$. $T_1 = 450 \text{ K}, T_2 = 360 \text{ K}$	$iv$. $0.5$

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