Practice question · Numerical answer
A Carnot engine has a hot reservoir at 600 K and an efficiency of 25 %. Compute the cold reservoir temperature in K.
Hints
- Rearrange the Carnot formula for the cold temperature.
- If efficiency is 0.25 then Tc/Th is 0.75, so Tc = 0.75 x 600.
Show the answer
450 (answers within ±5 count)
Why
gives K. Note how modest an efficiency a 150 K temperature drop buys.
Practise Cyclic Processes and the Carnot Cycle
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