JEE Mains · Physics · STD 11 - 11. thermodynamics
A Carnot engine whose heat \(\operatorname{sinks}\) 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 \(?\)
- A Increases by \(18\,^{\circ} C\)
- B Increase by \(200\,^{\circ} C\)
- C Increase by \(120\,^{\circ} C\)
- D Increase by \(73\,^{\circ}\)
Answer & Solution
Correct Answer
(B) Increase by \(200\,^{\circ} C\)
Step-by-step Solution
Detailed explanation
\(1-\frac{300}{ T }=0\) \(\frac{300}{ T }=0.75\) \(1-\frac{300}{ T }=0\) \(\frac{300}{ T }=0.75\) \(T =400 K\) If efficiency increased by \(\,100 \%\) then new efficiency \(\Rightarrow n ^{\prime}=50 \%\) \(1-\frac{300}{T^{\prime}}=0.5\) \(T^{\prime}=600 \,K\) Increase in temp…
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