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This is probably is stupid question but I think it must clear up some misconception I have. Magnets, presumably have magnetic fields. But where are the moving charges? Don't we need a current?

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marked as duplicate by ACuriousMind Feb 15 '17 at 20:00

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Most of the magnetism in a magnet comes from the magnetic dipole moment of the electrons orbiting its atoms. If we think of the electron as a small spinning charged sphere, then it is the spinning chrage that makes the current. Unfortunately this is a not a good model because the surface of the electron (assuming its "classical radius'') will be moving faster than the speed of light. For this reason Pauli originally did not believe in "spin" --- even though he gets most of the credit for the idea.

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  • $\begingroup$ For these dipoles, are there also an associated electric field. Is it just so small people don't talk about it? $\endgroup$ – CognisMantis Feb 15 '17 at 19:35
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    $\begingroup$ The electron does not appear to have an electric dipole moment of its own. A lot of effort is currently going into to to detect an electric dipole moment of the neutron. This if it exists must very tiny, but any non-zero value will violate both T (time) and P (parity) invariance. Quantum Chromodynamics has parameter that has no obvious reason to be zero but if not zero would give the neutron an electric dipole moment. $\endgroup$ – mike stone Feb 15 '17 at 19:44
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How do magnets work?

The subatomic particles electron, proton and neutron have magnetic dipole moments. This magnetic fields are intrinsic properties, means this fields exist under all circumstances. In nonmagnetic materials the sum of all magnetic dipole moments is zero.

In permanent magnets the sum over all this magnetic dipole moments is not zero. To produce strong magnets the material will be milled to powder and than pressed under the influence of a strong external magnetic field. During this production process some electrons are "frozen" with their magnetic fields, all in the same direction along the external magnetic field. Behind a certain temperature the and by the help of the thermic oscillations of the atoms the alignment of the magnetic dipole moments gets lost.

Now your question

Magnets, presumably have magnetic fields. But where are the moving charges

is answered in a way that moving charges are not involved.

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  • $\begingroup$ So take it the other way. How are moving charges involved in the induction of a magnetic field from a current carrying wire bended to a coil? It is conceivable that the magnetic dipole moments of the flowing electrons get aligned during their circular movement through the circular bended wire? $\endgroup$ – HolgerFiedler Feb 15 '17 at 19:38
  • $\begingroup$ One day I will send you how a magnet works. $\endgroup$ – John Duffield Feb 21 '17 at 18:53

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