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COP of refrigerator

  1. Nov 8, 2005 #1
    A vessel containing 8.43 kg of water at 21.1C is put into a refrigerator. The 0.1655 hp motor runs for 9 min to cool the liquid to the refrigerator's low temperature 4C.

    What is the COP of the refrigerator?

    = 123.463Wx540s
    = 66670.02 J

    COP = Qc/W

    Please Help.

    Thank you.
  2. jcsd
  3. Nov 8, 2005 #2

    Andrew Mason

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    The Coefficient of Performance for a refrigerator is defined as the ratio of the heat removed from the cold reservoir to the work added to the system. What is the work or energy input? (I think you have correctly worked this out based on one hp = 746 J/sec). What is the heat removed (in J.) ?

    Last edited: Nov 8, 2005
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