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Refrigerator- thermodynamics: how do i start?

  1. Apr 28, 2015 #1
    1. The problem statement, all variables and given/known data
    Newton’s Law of Cooling.

    A building is maintained at temperature TH with a reversible heat pump operating between the building and a colder environment at temperature TC < TH. The heat pump consumes electrical power at a constant rate W. The building also loses heat according to Newton’s law of cooling, that is, at a rate a(TH – TC) where a is constant. Show that the building temperature is maintained at temperature

    2. Relevant equations
    TH = TC + dW/dt (1/2a) [1 + sqrt( 1 + 4aTC/(dW/dt) )]

    3. The attempt at a solution
    Puzzled about how to start
  2. jcsd
  3. Apr 28, 2015 #2
    Hi, solved it using the coefficient of performance.
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