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Cooling of metal in vacuum

  1. Jan 26, 2010 #1
    If you put a piece of very hot metal in cold water the heat in the metal will transfer to the water until both are the same temperature. So the system water-metal still has the same initial energy.

    So my question is how does the piece of metal cool if it is put on a perfect vacuum.

    Is it electromagnetic waves that the metal emits or something like that?
  2. jcsd
  3. Jan 26, 2010 #2


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    Same way the sun transfers its heat energy to the earth - radiant, electromagnetic energy. A large part of such energy resides in the infrared spectrum of the EM radiation.

  4. Jan 26, 2010 #3
    Heat transfers via conduction, convection or radiation. Only the last is available in a perfect vacuum. Wikipedia likely has discussions on each.
  5. Jan 26, 2010 #4


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    What about sublimation? :tongue:
  6. Jan 26, 2010 #5


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    You mean ablation? Or I guess evaporation.

    That is the removal of the material itself, carrying away heat with it. I guess, technically, that is simply moving material around, not actually removing heat from the material.
  7. Jan 26, 2010 #6


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    I mean http://en.wikipedia.org/wiki/Sublimation_(chemistry [Broken]) - so your second guess is correct.

    If I have a hot piece of metal in vaccum and it loses part of the energy by evaporating itself, I would call it part of the cooling process, just like evaporation is part of the cooling process of the tea I have on my desk. This is just semantics and it depends on what we understand by "cooling piece of metal".
    Last edited by a moderator: May 4, 2017
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