Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Quick Conductor Question

  1. Apr 21, 2007 #1
    Why is it that BOTH electric AND magnetic fields are zero inside the conductor. My book says that the H-field is zero due to the fact that the E-field is zero but doesn't give any detailed explanation.
  2. jcsd
  3. Apr 21, 2007 #2


    User Avatar
    Science Advisor
    Gold Member

    I think you already saw the post regarding zero E field. In an ideal conductor any H field will induce eddy currents at the surface that perfectly cancel the magnetic field inside.
  4. Apr 21, 2007 #3


    User Avatar

    also, if you think about it using Maxwell's equations, if for a non-zero volume the E field is identically zero at all locations and in time, then there is no dE/dt as a source of a magnetic field. and because

    [tex] \nabla \cdot \mathbf{B} = 0 [/tex]

    there are no sole (monopole) sources of a magnetic field.
  5. Apr 22, 2007 #4
    Great! Thanks guys. :smile:
  6. Apr 22, 2007 #5


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Actually this is not entirely correct. According to *classical* EM, a perfect conductor cannot have any *change* in magnetic field, but it can have in principle a non-zero static magnetic field. It is a pure quantum effect that a superconductor cannot have a magnetic field inside. If it were a classical perfect conductor, it would simply "freeze in" the existing magnetic field at the moment of its transition to "perfect conductor".
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Quick Conductor Question
  1. Conductor question (Replies: 17)

  2. Quick question (Replies: 8)

  3. Quick question (Replies: 4)

  4. Quick question (Replies: 6)

  5. Quick question! (Replies: 2)