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Confused about electric field/velocity/magnetic field vectors

  1. Nov 1, 2011 #1
    So E=vB and {E}={v}cross{B} but if I have for instance v=5j and B=-1k, then E is in the positive i direction. Shouldn't it be in the negative direction? Thanks.
  2. jcsd
  3. Nov 1, 2011 #2
    Unless, I'm missing something, it's not true that E = v cross B.

    It's F = qv cross B if there is no electric field or F = q(E + v cross B) if there is an electric field.

    Unless you want to say that there is an electric field there that is exactly canceling the magnetic force. Then F = 0, and you get E = -v cross B. But that's a very specific situation.
  4. Nov 1, 2011 #3
    Are you talking about an electromagnetic wave?
    If this is the case, I think it is {E}=-{v}cross{B}, in the usual notations.
  5. Nov 1, 2011 #4
    Yes, F=qvXb or F=qvbsin(thata). Try using the right hand rule.

    1.) point hand in the direction of v
    2.) curl fingers in the direction of B
    3.) thumb points in the direction of the force
  6. Nov 1, 2011 #5
    I don't think this has much to do with the OP.
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