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If the COP of a heat pump is 7, then the COP of a refrigerator which is also working between the same high and low temperature is:

If the COP of a heat pump is 7, then the COP of a refrigerator which is also working between the same high and low temperature is: Correct Answer 6

CONCEPT:

S.No.

Refrigerator

 Heat pump
1.

A refrigerator is a device that maintains a system or a body at a temperature lower than the surrounding temperature.

A heat pump is a device that maintains a system or a body at a temperature higher than the surrounding temperature.
2.

In the refrigerator, the heat is removed from the low-temperature body and is rejected to the high-temperature body.

In the heat pump, the heat is removed from the low-temperature body and is added to the high-temperature body.
3.

Generally, the surrounding atmosphere acts as the high-temperature body for a refrigerator.

Generally, the surrounding atmosphere acts as the low-temperature body for a heat pump.

Coefficient of Performance:

  • The coefficient of performance is defined as the ratio of the desired output to the work input.

EXPLANATION:

Given COPHP = 7

  • We know that when a refrigerator and a heat pump are working between the same low and high temperature, the relation between the coefficient of performance of the refrigerator and the heat pump is given as,

⇒ COPHP = COPR + 1

⇒ COPR = COPHP - 1

⇒ COPR = 7 - 1

⇒ COPR = 6

  • Hence, option 3 is correct.

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