Check Your Understanding What is the efficiency of a perfect
The efficiency of a perfect heat engine and the coefficient of performance of a perfect refrigerator.
Explanation of Solution
Introduction:
A device which is used to extract heat from the source and convert it into mechanical work is known as a heat engine. A perfect heat engine is the one that converts all its heat input into the work. A perfect refrigerator transports heat from a cold reservoir to a hot reservoir without work input.
The efficiency of the heat engine is the ratio of the work done and the heat input. Since a perfect heat engine converts all the input heat into mechanical work, then the efficiency of the perfect heat engine is
Conclusion:
Therefore, the efficiency of a perfect heat engine is
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