Can an EMF Induce a Magnetic Field in a Moving Metal Rod?

AI Thread Summary
Moving a metal rod in a magnetic field induces an electromotive force (emf), but this emf itself does not produce a magnetic field. Instead, the induced emf can generate a current, which in turn creates a magnetic field that opposes the original field. The discussion emphasizes that for an emf to induce a magnetic field, there must be a movement of charges, specifically electrons, within the rod. It is noted that a constant motion of the rod does not lead to an induced magnetic field unless there is a change over time. Ultimately, magnetic fields are produced by currents or moving charges, not directly by the emf alone.
lockerman2007
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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 ??
 
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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.
 
haiha said:
If you move a metal rod in a magnetic field, an emf is induced. But that emf does not create any magnetic field.

unless it is changing w.r.t. time.
 
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 ?
 
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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