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Heat transfering from Cold to Hot?

  1. Sep 12, 2010 #1
    Is it possible for heat to transfer from a colder atom (slower moving) to a hotter atom (faster moving)

    I know that hot and cold are not really appropriate words to be using here.


    My reasoning is from kittel thermal physics,

    From an entropy standpoint,
    The most probable configurations will dominate the statisical properties of the combined system, most probable confiigurations are ones that maxmimize the entropy.

    For Large N, there is a sharp peak of configurations that have maximal entropy, but what about for small N?

    Is it possble to conceive two small N systems where when combined, the maximal entropy corresponds to a situation where the colder object actually gives heat to the warmer object, opposite of the normal directional flow of heat?


    Isn't is possible for a collision between a slow moving atom and a fast moving atom to result in the faster moving atom gaining more kinetic or thermal energy. From a probabilistic picture, this should technically be possible. Isn't this the same idea?


    Thanks
     
  2. jcsd
  3. Sep 12, 2010 #2
    Here's how a slow moving particle can give energy to a faster moving one:

    http://4.media.tumblr.com/PrbyDnKQQk69dz9tpx8QZc1ao1_500.png [Broken]
     
    Last edited by a moderator: May 4, 2017
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