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Temperature/Kinetic Energy Question

  1. May 18, 2005 #1
    Just a quick question:

    I have always been told that the temperature of a substance was a measurement of the average kinetic energy of the molecules. If I were to throw a ball in space (i.e no air resistance), does this mean the ball now has a higher temperature since it is moving faster and all its molecules have a higher kinetic energy?

  2. jcsd
  3. May 18, 2005 #2
    I suppose the possible difference would be neglible. Divide the KE gain over all the atoms in the ball and you're going to get a really really really small number.
  4. May 18, 2005 #3

    Doc Al

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    Staff: Mentor

    No. Temperature is a measure of the average KE of the molecules measured from a frame in which the center of mass of the object is at rest. (Otherwise temperature would be frame dependent.)

    You might find this discussion helpful: https://www.physicsforums.com/showthread.php?t=75824
  5. May 18, 2005 #4
    Damn it. That's what I get for not thinking things through before posting. And it's so obvious too.
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