Question
No real engine can have efficiency greater than that of a Carnot engine working between the same two temperatures, why?
✓
Answer
A Carnot engine is an ideal heat engine from the following points of view:
- There is absolutely no friction between the walls of cylinder and the piston.
- The working substance is an ideal gas. In a real engine, these conditions cannot be fulfilled and hence no heat engine working between the same two temperatures can have efficiency greater than that of Carnot engine.
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