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

Magnetic field question

  1. Jun 17, 2013 #1
    This is a problem from Reitz-Milford-Cristy-Problem 9.15(fourth Ed.) , I know the answer but I do not know how to justify it.There is a long wire carrying a current "I" above a plane,inside the plane we have to cases a)μ=∞; and b)μ=0. We must find the field above the plane. To solve the problem we split the field sources: 1)wire + 2)Magnetic plane. Part 1) is already known and to find 2) we put H=-grad∅ and solve laplace equation Δ∅=0. To solve the problem we consider an image current in case a) it is a parallel current and in case b) it is an antiparallel one.
    I understand case b), in this case we have B=0 inside the plane so the normal component of H must vanish so the normal derivate of ∅ must cancell that of "I" and problem is uniquely solved.
    However in case a) we have H=0 and the tangencial component of H must vanish, we can do this with a parallel image however in this case what we know is the tangencial derivate of ∅ and unicity theorem for laplace equation does not apply.
    Can someone shed some light on this?(I hope my english is understandable)
    Last edited: Jun 17, 2013
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted

Similar Discussions: Magnetic field question