Physics · 2019
JEE Main · 10 January 2019, Shift 1 · Q10
Three Carnot engines operate in series between a heat source at a temperature T_1 and a heat sink at temperature T_4 (see figure). There are two…
Three Carnot engines operate in series between a heat source at a temperature $\displaystyle \mathrm{T}_1$ and a heat sink at temperature $\displaystyle \mathrm{T}_4$ (see figure). There are two other reservoirs at temperature $\displaystyle \mathrm{T}_2$ and $\displaystyle \mathrm{T}_3$, as shown, with $\displaystyle T_1>T_2>T_3>T_4$. The three engines are equally efficient if :
Official answer
(3)
$\displaystyle \mathrm{T}_2=\left(\mathrm{T}_1^2 \mathrm{~T}_4\right)^{1 / 3} ; \mathrm{T}_3=\left(\mathrm{T}_1 \mathrm{~T}_4^2\right)^{1 / 3}$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.