Finding B, M, and H for an infinite conducting slab

AI Thread Summary
The discussion centers on solving a homework problem involving an infinite conducting slab with a specified current density and magnetic susceptibility. The key equations referenced include Ampere's law and the definitions of the magnetic fields H, B, and the magnetization M. The main challenge is determining the correct approach to find the auxiliary field H, particularly in defining an appropriate Amperian loop, given that the current density is zero when integrated across the slab. There is confusion about whether the opposing currents in the slab will result in H being zero. The participant seeks guidance on how to proceed with the calculations effectively.
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Homework Statement


We have an infinite slab of conducting material, parallel to the xy plane, between z = −a and z = +a, with magnetic susceptibility χm. It carries a free current with volume current density J = J0z/a in the x direction (positive for z > 0, negative for z < 0). The integrated current density across the whole slab is therefore zero. What are H (auxiliary field), B (magnetic field), and M (magnetization) (magnitude and direction)? What is the bound current?

Homework Equations


Ampere's law: ∫B⋅dl=μ0*Ienc
Magnetic dipole moment: m=I*a
Bound currents: Jb=∇×M (volume bound current) and Kb=M×n (surface bound current)
Definition of H: H=(1/μ0)*B-M
Ampere's law in terms of H: ∫H⋅dl=Ifenc

The Attempt at a Solution


I'm not really even sure where to start with this one. I thought finding the magnetization was what I needed to do as a starting point but I'm not entirely sure how to do that. I also was wondering if my starting point should be to find H by defining an Amperian loop inside the slab, but I'm also unsure of how to do that because the current is equal in magnitude and opposite in direction in the top and bottom sections of the slab so won't it just cancel out giving me an result of H = 0? If anyone could point me in the right direction it would be appreciated.
 
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