In a vapor compression refrigeration loop, the ratio of heat absorbed in the evaporator to heat rejected in the condenser is_________________?
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Answer: B. less
Explanation
In a vapor compression refrigeration cycle, heat rejected in the condenser equals evaporator heat absorption plus compressor work input, making the ratio less than one. Energy conservation dictates that the condenser heat output exceeds evaporator heat input by the exact amount of compressor work. Dividing evaporator heat absorption by a larger condenser heat rejection value yields a mathematical ratio below unity. The first law of thermodynamics applied to a refrigeration cycle balances total energy entering and leaving the system. Compressor work input adds mechanical energy to the refrigerant vapor, increasing the total heat discharged outdoors. Refrigeration performance metrics rely on energy balances between low-temperature evaporators and high-temperature condensers.
A ratio greater than one is thermodynamically impossible because condenser heat rejection must always exceed evaporator heat absorption. Stating that the ratio is the same ignores the fundamental addition of mechanical work input from the compressor. System capacity variations do not alter the fundamental thermodynamic law requiring condenser heat to exceed evaporator heat.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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