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

In summary, the problem involves an infinite slab of conducting material with magnetic susceptibility χm, carrying a free current with volume current density J = J0z/a in the x-direction. The integrated current density across the slab is zero. The task is to find H (auxiliary field), B (magnetic field), and M (magnetization) (magnitude and direction), as well as the bound current. To solve this, Ampere's law in terms of H can be used, along with the definition of H and the bound currents equations. The first step is to define an Amperian loop inside the slab and use Ampere's law to find H.
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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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Someone please help me. I have no idea what I'm doing and need to get this assignment done ASAP. I know now that I need to find H first using Ampere's law but am having a hard time understanding how to define my Amperian loop
 

1. What is the purpose of finding B, M, and H for an infinite conducting slab?

The purpose of finding B, M, and H is to understand the behavior of electromagnetic fields in an infinite conducting slab. This information is useful in many applications, such as designing antennas and electromagnetic shielding.

2. How do you find the values of B, M, and H for an infinite conducting slab?

The values of B, M, and H can be found by solving Maxwell's equations, specifically the boundary conditions at the interface between the conducting slab and the surrounding medium. This involves setting up and solving mathematical equations using specialized techniques.

3. What factors affect the values of B, M, and H for an infinite conducting slab?

The values of B, M, and H are affected by the thickness of the slab, the material properties of the slab and surrounding medium, and the frequency of the electromagnetic field. These factors can alter the behavior of the fields and must be taken into account in the calculations.

4. Can the values of B, M, and H be calculated for a finite conducting slab?

Yes, the values of B, M, and H can also be calculated for a finite conducting slab. However, the equations and techniques used may be more complex and may require numerical methods to solve. The properties of the finite slab, such as its length and width, will also need to be considered in the calculations.

5. What are some real-world applications of finding B, M, and H for an infinite conducting slab?

As mentioned earlier, the values of B, M, and H for an infinite conducting slab are useful in designing antennas and electromagnetic shielding. They are also important in understanding the behavior of electromagnetic waves in materials, which has applications in industries like telecommunications, electronics, and medical imaging.

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