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Is there any effect of wire's insulation on it's magnetic an

  1. Jan 7, 2015 #1
    Does insulation affect electric and magnetic field?
  2. jcsd
  3. Jan 7, 2015 #2


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    What's the purpose of insulating a wire?
  4. Jan 7, 2015 #3
    That is what i'm asking.If it does,why a magnet interacts it?i'm confused.please explain it??
  5. Jan 7, 2015 #4


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    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

  6. Jan 7, 2015 #5


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    I'm not sure that a magnetic field on its own is affected by insulation
    That I would have to research
  7. Jan 7, 2015 #6


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    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).
  8. Jan 7, 2015 #7
  9. Jan 8, 2015 #8
  10. Jan 17, 2015 #9


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    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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