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Heat flow

  1. Jun 24, 2014 #1
    If heat flow is the momentum change from a faster moving atom or molecule to a slower moving one, and momentum is mass x velocity is it possible - for a very limited amount - for heat to flow from a slower (colder) heavy atom to a faster moving (hotter) atom ?
  2. jcsd
  3. Jun 24, 2014 #2

    Philip Wood

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    Gold Member

    (1) It's energy transfer, not momentum transfer, that's relevant.

    (2) It is, I believe, possible in an oblique collision for a faster molecule to pick up speed (and hence KE) from a slower molecule of the same mass.

    (3) But we wouldn't classify this as a flow of heat. To constitute a flow of heat we'd need a net transfer of energy for many molecules.
  4. Jun 24, 2014 #3
    I was confusing energy change and momentum change alright

    Thanks Philip
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