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Speed of Atoms

  1. May 3, 2009 #1
    How fast does an atom vibrate in m/s. I have found how fast it vibrates in hz but I'm trying to convert that to speed. Thanx.
  2. jcsd
  3. May 4, 2009 #2


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    You can't express a frequency in m/s

    Frequency is expressed in Hz, or /s. The units are not compatible.
  4. May 4, 2009 #3
    You can get a rough estimate by assuming the vibrations are simple harmonic.The velocity varies between zero and a maximum of 2pi*frequency*amplitude of vibration.(as matterwave pointed out it was probably the frequency that you found)
  5. May 4, 2009 #4
    Thermal neutrons (mass = 1 AMU) have an rms velocity of about 2200 meters per second at room temperature. Heavier molecules like N2 have an rms velocity of 2200/sqrt (28)where 28 is the gram molecular mass of nitrogen molecule. The relation is (1/2) m v2 = kT where k is Boltzmann's constant and T is in kelvin.

    Boltzmanns constant = 1.38 x 10-23 Joules per degree kelvin
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