The efficiency of a real heat engine compared to a Carnot engine operating between the same temperatures is:
Correct answer: B. Always lower
- A. Always higher
- B. Always lower
- C. Equal
- D. Sometimes higher
Explanation
A real heat engine has irreversibilities (e.g., friction, heat loss), making its efficiency lower than that of an ideal Carnot engine operating between the same temperatures.
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About Energy Losses and Efficiency
Efficiency compares useful output energy or power with the total input, usually expressed as a percentage. The topic covers energy losses through friction, heating, resistance and sound, along with power ratings and Sankey diagrams. Efficiency is not the same as conservation of energy, because lost energy is transferred rather than destroyed.
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