Does insulation affect electric and magnetic field?
What's the purpose of insulating a wire?
That is what i'm asking.If it does,why a magnet interacts it?i'm confused.please explain it??
Insulation does affect the EM propagation speed along the outside of a wire
This becomes very apparent with transmission lines ( antennas) that have either a covering
The result is a slowing of the EM propagation, This is known as the VF -- Velocity Factor
I'm not sure that a magnetic field on its own is affected by insulation
That I would have to research
Why do you think a magnetic field interacts with insulation? It does not. As stated already, insulation has a higher dielectric constant than air, so it will affect the E field generated by voltages on the wire (including the velocity factor that Dave has mentioned).
Insulation is typically dielectric, so it will affect the electric fields a lot more than the magnetic fields.
The magnetic permeability is materials that would be used for insulation is very very small
I guess if you're counting a sheath (like in coaxial cable) as the insulation, then it certainly affects the [itex]B[/itex] field produced by the wire because the metal intentionally has high permeability. Otherwise plastic wouldn't have a noticeable effect.
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