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Electron collision

  1. Feb 21, 2009 #1
    As explained by Max Plank for every orbit having two electrons in
    it, have 2 spins quantum numbers. And they are always 1/2 and
    -1/2.It just means that the two electrons move in opposite
    directions in orbit. Then why don’t they collide?
  2. jcsd
  3. Feb 21, 2009 #2


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    No it was not Planck.

    Secondly, the spins does not mean that they move in opposite directions.

    Third, electrons does not orbit around the atomic nucleus as planets around the sun.
  4. Feb 21, 2009 #3
    Everything malawi_glenn says is true. Electrons are point like particles which exert repulsive electric forces. As the distance between the electrons goes to zero, the repulsive force becomes infinite. In addition to the electromagnetic forces, electrons are fermions (spin 1/2) and so they experience a purely quantum mechanical effect called an exchange force which prevents them from being "in the same state." The tricky thing is that, in quantum mechanics, being in the same statedoes not mean being in the same position. Electron states in an atom are determined by four numbers, which are usually chosen to be energy, total anular momentum, orbital anglar momentum in one direction, and spin angular momentum in one direction. Exchange forces prevent any two electrons from having the same four numbers, and this is why two electrons ith the same energy and angular momentum must have different spins.

    Edit: Sorry for the typos, keyboard problems.
  5. Feb 22, 2009 #4


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    I received this message:

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