The performance of a refrigerator is described by________________?
Correct answer: B. coefficient of performance
- A. efficiency
- B. coefficient of performance
- C. both A and B
- D. not described
Explanation
A refrigerator is assessed by its coefficient of performance, COP = heat removed from the cold space ÷ work input, rather than by heat-engine efficiency. The likely mistake is choosing efficiency because both compare useful output with energy input, but a refrigerator transfers heat instead of converting heat into work.
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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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