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Electron spin/magnetism

  1. Apr 27, 2005 #1
    First of all, um, do electrons actually spin (in the classical sense)? If not, how do they possess angular momentum? From their orbit around the nucleus??

    And how is all of that related to magnetism? (I.E. why does a spinning charged body interact with a magnetic field?)

    I've read some stuff online, but none of it had a satisfying explanation.

    Thank you! :smile:
  2. jcsd
  3. Apr 27, 2005 #2

    James R

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    In a classical sense, electrons appear to have no size, so it doesn't really make sense to say that they spin. However, if we model an electron as having finite size, and model the charge of the electron as orbiting the centre of the electron, then the effects of that orbiting charge are similar to what we would expect for any classical orbiting charge. The charge has angular momentum, and an associated magnetic moment.

    In quantum mechanics, it still makes sense to assign angular momentum to the electron, even though the electron is no longer considered to be like a little billiard ball (as it is in classical physics). A magnetic moment is still associated with the electron's angular momentum, in exactly the same way that it would be if the electron was a classical object.

    To relate angular momentum with magnetism, the best way to think of it is to consider a charge moving in a small circle around a point in space. That charge produces a magnetic field, which can interact with other magnetic fields around it.
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