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Time varying magnetic field and electron

  1. Jun 17, 2010 #1
    I am a bit depressed, I have just finished my PhD as a physicist and cannot work out this simple question.

    I am trying to find out what happens to a static electron in a time varying magnetic field.

    This is my understanding:

    There are two laws, the Lorentz's force, for moving charges, and the Faraday's Law for time varying magnetic fields.

    The electron is not moving, therefore v=0, and Lorentz force = 0

    From the Faraday's law, a time varying magnetic field creates a flow of electrons on a closed circuit. But I am not sure what happens to a lonely charge.

    Any help and or corrections is appreciated.

  2. jcsd
  3. Jun 17, 2010 #2


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    If there is a time-varying magnetic field, then there is an electric field, so the Lorentz force is not zero.
  4. Jun 17, 2010 #3
    I see. Thanks, I was in fact looking at an incomplete formula for the Lorentz formula, without the q E component.

    I will try and workout what the E field looks like.

    Thanks for your help phyzguy.
  5. Jun 17, 2010 #4
  6. Jun 17, 2010 #5


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    [tex]\nabla\times{E} = -\frac{\partial{B}}{\partial{t}}[/tex]
  7. Jun 17, 2010 #6
    Extra credit: if B=-t along the positive Z axis, what is the resulting force on an electron located at the origin?
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