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Heat pump performance: COP magnitude relative to unity Complete the statement about a heating-mode device: “The coefficient of performance (COP) of a heat pump is always ___ one (for normal operation).” Choose the correct completion.

Q: Heat pump performance: COP magnitude relative to unity Complete the statement about a heating-mode device: “The coefficient of performance (COP) of a heat pump is always ___ one (for normal operation).” Choose the correct completion.

Concept COPHP = QH/W = 1 + QL/W = 1 + COPRef > 1 for any functioning heat pump, since some of the delivered heat is the absorbed heat plus the input work. Final Answer greater than.

Difficulty: Easy

less than
equal to
greater than
unpredictable and may be less than or greater than

Correct Answer: greater than

Explanation:

Concept
COP_HP = Q_H/W = 1 + Q_L/W = 1 + COP_Ref > 1 for any functioning heat pump, since some of the delivered heat is the absorbed heat plus the input work.

Final Answer
greater than.

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