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Radiation vector for a short dipole near a perfect magnetic conductor

  1. Nov 13, 2012 #1
    Hi there.

    If I wanted to calculate the radiation vector (in z > 0) produced by a short dipole with uniform current Io (+z direction) on a infinite perfect electric conductor (plane z=0), I'd have to apply the images method. So I'd have to calculate the radiation vector produced by two short dipoles, one in z > 0 and one in z < 0, with currents Io.

    However, if we change the perfect electric conductor by a perfect magnetic conductor, how can I apply the images method?

    Thank you.
  2. jcsd
  3. Nov 13, 2012 #2


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    Staff: Mentor

    What's a perfect magnetic conductor?
  4. Nov 13, 2012 #3
    It's an idealization.

    PEC (Perfect Electric Conductor): [itex]\hat{n}\times\vec{E}=0 [/itex] and [itex]\hat{n}\times\vec{H}=\vec{J}_s[/itex].

    PMC (Perfect Magnetic Conductor): [itex]\hat{n}\times\vec{E}=-\vec{M}_s [/itex] and [itex]\hat{n}\times\vec{H}=0[/itex].

    Thank you.
  5. Nov 14, 2012 #4
    At very low frequency, mumetal of permalloy are good magnetic conductors.

    It would change the sign of the current in the image. Opposite current achieve zero magnetic field at the magnetic conductor, while same currents achieve zero electric field.
  6. Nov 20, 2012 #5

    I understand what you say, but, in that case, radiation vector is 0 (because currents are opposite), isn't it?

    Thank you.
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