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Carnot refrigerator and II law of Thermodynamics

  1. Jan 2, 2012 #1
    As per II law of thermodynamics you it is NOT possible that a hotter body becomes hotter and colder body becomes colder when in contact. But in a Carnot refrigerator, the heat is taken from a cold reservoir and pushed to a hotter one. It sort of opposite the II law. Help me over this paradoxical situation.
  2. jcsd
  3. Jan 2, 2012 #2
    There is an input of work in the carnot refrigerator.

    The second law of thermodynamics states that heat does not flow from a cold reservoir to a hot reservoir spontaneously. However, heat may flow from a cold reservoir to a hot reservoir with the input of work.
  4. Jan 2, 2012 #3


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    Staff: Mentor

    From the outside it might look like heat moves against a thermal gradient, but if you look at the processes, you'll see it never does.
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