Question

What is it in an electric current that produces a magnetic field?

Answer 1

I believe it has to do with quantum physics. There's a good wikipedia article: http://en.wikipedia.org/wiki/Magnetic_field Hope it helps!

Answer 2

Here's an intriguing article also: http://en.wikipedia.org/wiki/Relativistic_electromagnetism

But thanks!

Answer 3

Electric and magnetic fields are very intimately tied together, and relativistically turn out to be two superficially different aspects of one phenomenon. They're two sides of the same coin. As far as what "in" an electric field does it, it's nothing in particular.... the electric and magnetic fields themselves are the entities that you talk about.

Answer 4

OK, I speculated that the reason may be similar to ferromagnetism (the imbalance of up spin over down spin due to half filled electron shells, I gather), that somehow the electric current causes the electrons to spin in the same 'direction'.

Answer 5

In what way does relativity amalgamate electricity and magnetism (moreso than Maxwell's equations did)?

Answer 6

No, ferromagnetism is a quantum mechanical phenomenon whereby large groups of atoms, called magnetic domains, all spin in the same direction. These domains flip as a whole, and the alignment of a large proportion of these domains produces a comparatively tremendous magnetic field.

Answer 7

In relativity, one deals with transformations between different reference frames, i.e. how physics would appear to different observers moving at different constant speeds. If I'm sitting next to a point charge, I see an electric field and no magnetic field. If, however, I'm riding by on a skateboard, the charge appears to move relative to my frame, which constitutes a current, so I also see a magnetic field. In general, when going from one reference frame to another, electric fields and magnetic fields get mixed up.

Answer 8

Magnetic domains cause large-scale materials to be magnetic, but is it incorrect that the magnetism of an individual atom is caused by an imbalance of spin up/down electrons?