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Why are atoms in constant motion?

  1. Oct 8, 2009 #1
    Why are all atoms in constant motion? It is just a fundamental phenomena of our world? Can someone explain the theory behind this?

    Why does decreasing/increasing the "temperature" affect the speed (kinetic energy) of atoms? Again, can someone explain the fundamental theory behind this?
  2. jcsd
  3. Oct 8, 2009 #2
    All atoms are in constant motion because this universe has energy of some kinds.
    Temperature is just a concept that human beings use to describe the movement of atomes/molecules. When we "increase temperature", it's nothing other than we increase the movement of the molecules somehow, say put an electric heater under the kettle: the high movement of the atoms in the heater will transfer to the kettle and then the water inside it.
  4. Oct 8, 2009 #3
  5. Oct 9, 2009 #4
    Concept of temperature does put things in the right context. The lowest energy state where the matter cannot transfer energy to other matter because it is not vibrating fast enough, is called absolute zero in thermodynamics (which studies phenomena at molecular level.)

    Atoms in motion is just the expression thermal of energy/temperature around us. At sub molecular level, there are a much more fundamental things that need quantum mechanics for explanation.
  6. Oct 9, 2009 #5

    Andy Resnick

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    I'm not sure they are- at least, I don't understand how the concept of velocity carries over to quantum mechanics. I'm not sure there is even a quantum-mechanical definition of velocity that correlates with the classical picture of tiny little balls jiggling around.
  7. Oct 10, 2009 #6
    Imagine that when you snapped your fingers the atoms could start and then continue to slow down.The temperature would drop the atmosphere would sink and depending on the pressure parts of it could liquify and solidify.The oceans and rivers and all living things would freeze and blah blah blah.Moral,don't snap your fingers.:cry:
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