Refrigeration cycle energy balance: compare heat rejected and heat absorbed In a vapor-compression refrigerating machine, how does the condenser heat rejection compare to the evaporator heat absorption? Choose the correct relation.
Mechanical Engineering
Heat Transfer, Refrigeration and Air Conditioning
Difficulty: Easy
Choose an option
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AHeat rejected is greater than heat absorbed
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BHeat rejected is less than heat absorbed
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CHeat rejected equals heat absorbed
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DNo fixed relation between them
Answer
Correct Answer: Heat rejected is greater than heat absorbed
Explanation
Concept/ApproachFirst law over the cycle gives: QH = QL + Win, where QL is heat absorbed in the evaporator, Win is compressor work, and QH is heat rejected in the condenser.
ImplicationSince Win > 0 for a working refrigerator, QH > QL.
Final AnswerHeat rejected is greater than heat absorbed