Is magnetic field affected by metal conductor?

repulsed by bismuth attracted by iron little effect by tin

different effects if magnetic field is dynamic

Depends on metal. A ferrous metal (like iron) WILL distort field lines. A non ferrous conductor like copper or aluminum will not affect a STEADY or DC magnetic field, but because of induction WILL effect an AC magnetic field.

Curiously, however, it will affect the field in the opposite direction to the effect of a ferrous metal.

Metals get involved with magnetic fields in two possible ways. All metals (and anything else with a finite conductivity) circulate current as any magnetic field passing through it changes strength. The circulating current creates a mirror image magnetic field that partially cancels the one trying to penetrate the metal. For any non superconducting metal, this process also consumes energy from the field. These circulating currents are referred to as eddy currents.

Ferromagnetic metals (ones that are attracted to a magnet) also have another effect. They act as a short cut for any magnetic field that lasts long enough for the above effect to fade out, at least for field strengths below their saturation limit. In other words, it takes more work to create a given flux in air than it does to create the same flux through iron. Since any effect that causes the total amount of flux to increase, generates a force in the direction of motion that allows the increase, this short cut effect is what causes iron to be attracted to a magnet. The work the magnet can do in attracting the iron is the work it took to build the field in air minus the lesser work it takes to build that field through iron.

Things get more complicated for electromagnetic waves. Both the electric field and magnetic field components of waves move surface charges around as they pass by or reflect off of conductors. Maxwell's equations are the most compact description that covers all these possibilities.

That's enough hand waving for now. My arms are tired. ;-)

Yes.

Yes.

If you ask what is the effect of a conductor on a magnetic field, then: Because metal conducts, it tends to block, divert, change the electric field.

A changing magnetic field induces current in a conductor which in turn causes a magnetic field that opposes the original magnetic field. This new magnetic field sums with the original to form a completely new magnetic field.

Currents are induced in the conductor which sum to arrive at a completely new electromagnetic field around the conductor.

You are welcome, 73, Steve, K,9.D;C'I

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I'm not convinced. Who is Maxwell anyway?

The worst nightmare of many an engineering student?

Conversely, a moving conductor interacts with a static magnetic field.

Fred

Heheh.

Good answer Doug!