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Homework Help: Magnetic Moment, Electron Spin, Energy

  1. Oct 26, 2008 #1
    1. The problem statement, all variables and given/known data

    The PE of a magnetic moment in an external magnetic field is given by U = -u dot B. Calculate the difference in energy between the two possible orientations of an electron in a magnetic field B = .6k T

    2. Relevant equations

    3. The attempt at a solution

    I realize electrons can have an up spin and down spin, but I am having a hard time doing this problem.

    I believe I should be using g = 2 for the gyromagnetic ratio. So: (_h = h bar)
    uz = -g uB JZ/_h
    uB = e(_h)/(2me)

    Unfortunately then I don't know what I should have for Jz. (This is defined by my book as "any type of angular momentum).

    So I guess my problem is that I don't know what I should use for angular momentum, since n and l aren't defined in the problem. Can anyone help clear this up?
  2. jcsd
  3. Oct 26, 2008 #2
    Use the electron spin, S_z. Strange you would know about the gyromagnetic ratio but not about which angular momentum that refers to in the case of an electron!
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