A Carnot engine whose heat sinks at 27$^\circ$C, has an efficiency of 25%. By how many degrees should the temperature of the source be changed to increase the efficiency by 100% of the original efficiency?
Solution
<p>Initially : ${1 \over 4} = 1 - {{300} \over {{T_H}}}$</p>
<p>$\Rightarrow {T_H} = 400\,K$</p>
<p>Finally : Efficiency becomes ${1 \over 2}$</p>
<p>$\Rightarrow {1 \over 2} = 1 - {{300} \over {T{'_H}}}$</p>
<p>$\Rightarrow T{'_H} = 600\,K$</p>
<p>$\Rightarrow$ Temperature of the source increases by 200$^\circ$C.</p>
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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