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Production of magnetic field

  1. Feb 16, 2007 #1
    I want to ask a question about magnetic field.
    If I move a metal rod in a magnetic field, an emf is induced in it,
    will the emf produce a magnetic field ?
    Actually, a magnetic field is produced by an electric field or a current ??
  2. jcsd
  3. Feb 16, 2007 #2
    If you move a metal rod in a magnetic field, an emf is induced. But that emf does not create any magnetic field. The emf can create current and in turn current will create magnetic field. The induced magnetic field will be against the original field. That's why when you plug in loads into a DC generator, the torque will be harder.
  4. Feb 16, 2007 #3


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    unless it is changing w.r.t. time.
  5. Feb 16, 2007 #4
    That means the movement of electrons produce a magnetic field ?
    Can we consider that for a emf to be induced, electrons should move to one side of the rod and at this small instant, a magnetic field is produced ?
  6. Feb 16, 2007 #5
    Let immagine the magnetic field is infinite large, and the rod is moving for ever, so the emf is induced, but not any induced magnetic. Magnetic field is only caused by current or moving charges.
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