The efficiency of a Carnot cycle is determined by________________?
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Answer: D. temperature range of operation
Explanation
Carnot efficiency depends exclusively on the absolute temperatures of the heat source and sink. Operating temperature limits dictate the maximum theoretical conversion of heat into work. The working medium properties do not affect the efficiency of an ideal Carnot cycle engine. The Carnot cycle establishes the absolute upper limit for heat engine thermal efficiency. Efficiency formula uses absolute temperatures Kelvin for both high-temperature source and low sink. Reversible isothermal and adiabatic processes make up the idealized Carnot cycle stages.
Power plant engineers strive to raise boiler operating temperatures to maximize Carnot efficiency limits. Environmental cooling water temperatures restrict the lower sink temperature limit in thermal stations. Carnot efficiency provides a benchmark to evaluate how close real-world engines approach perfection. Option A is incorrect because Carnot efficiency is independent of the working fluid properties. Option B refers to engine physical condition rather than fundamental thermodynamic cycle limits. Option C and E describe practical operational factors rather than the governing temperature range.
- Subject
- Engineering
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- Mechanical Engineering
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- Difficulty
- medium
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