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Heat at work

  1. Sep 3, 2004 #1
    Why do atoms move faster in a higher temperature?
    If an atom was initially not moving at all, and then heat was applied to it, would it start moving? If so, what direction will it move in?
  2. jcsd
  3. Sep 3, 2004 #2


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    It is not possible for an atom to not be moving at all, except at absolute zero, which is unobtainable.

    Atoms move faster at higher temperatures because that is how we define temperature. Temperature is related to the average kinetic energy of particles in a substance. The higher their kinetic energy (the faster they are moving), the faster will be the measurement of the thermometer.

    "Heat" and "temperature" are statistical concepts which apply to large collections of atoms simultaneously. It is not very sensible to describe a single atom as having a temperature; nor is it sensible to talk about applying heat to one single atom.

    - Warren
  4. Sep 3, 2004 #3
    OK... Thats understood, but it raises 2 questions.
    1. What direction do the atoms go? Or do they just bounce off other atoms?
    2. Do only the atoms move around from kinetic energy, or do individual particles like protons, nutrons, and electrons move also?
  5. Sep 5, 2004 #4
    1) The direction of the atoms are completely random according to the Kinetic Molecular Theory.

    2) Only the atoms move, the protons and neutrons are fixed in the atom as being the nucleus with electrons "rotating" around the nucleus. If the atoms move fast enough, some atoms will get ionized (they will lose 1, some, or all electrons).
  6. Sep 5, 2004 #5
    No, I mean if the particles are not in an atom.. Individually floating around. Would they move from heat, or only atoms affected by it?

    Btw, thanks for the replies. It answers a couple of questions. :smile:
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