Physics · 2020
JEE Main · 7 January 2020, Shift 2 · Q7
Two ideal Carnot engines operate in cascade (all heat given up by one engine is used by the other engine to produce work) between temperatures, T_1…
Two ideal Carnot engines operate in cascade (all heat given up by one engine is used by the other engine to produce work) between temperatures, $\displaystyle \mathrm{T}_1$ and $\displaystyle \mathrm{T}_2$. The temperature of the hot reservoir of the first engine is $\displaystyle \mathrm{T}_1$ and the temperature of the cold reservoir of the second engine is $\displaystyle \mathrm{T}_2$. T is temperature of the sink of first engine which is also the source for the second engine. How is T related to $\displaystyle \mathrm{T}_1$ and $\displaystyle \mathrm{T}_2$, if both the engines perform equal amount of work ?
Official answer
(2)
$\displaystyle \mathrm{T}=\frac{\mathrm{T}_1+\mathrm{T}_2}{2}$
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