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magnetic field under block of iron

Consider an ideal magnet with even field across its pole's surface and a block of iron over it (fig B). (Disregard the "moving coil" for now)

The question is: Is the magnetic field between the iron block and magnet any different than elsewhere across the magnet's pole?

In other words:
From what I understand, if you move a coil through a uniform magnetic field (Fig A) (not in and out of the field), the coil does not produce any electricity. (Am I right?)
Would the coil produce electricity in (Fig B) if moved under the iron block and away from the block?

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The field lines emanating from the magnet would be significantly distorted by the presence nearby of a chunk of iron. You can think of the iron as having a tendency to "collect up" the field lines, and in the process it becomes (temporarily) another magnet, with its "s" end facing the other magnet's "n" end.

If the coil is moved in such a way that the wires in it do not "cut through" any of the field lines of the nearby magnet as they move, then no current is induced in the coil.

Moving the coil back and forth between the iron block and the magnet (under and away, as you put it) then a current will definitely be induced in the coil.

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  • $\begingroup$ "If the coil is moved in such a way that the wires in it do not "cut through" any of the field lines of the nearby magnet" - What do you mean? How can you move a coil thru a magnetic field without "cutting through field lines" ? Is it that if the field is uniform all across then we consider that there are no "lines" to be crossed? $\endgroup$ – Alex Doe Jan 7 at 3:17
  • $\begingroup$ I would like to accept your answer, but before I do that, do you know of any articles online that I can read that would support your claims? $\endgroup$ – Alex Doe Jan 19 at 11:16

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