(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The question is Jackson's 5.35. Insulated coil on a sphere (radius a) to generate uniform field B0 in the z-direction inside the sphere and dipole field outside the sphere. Conductivity is [tex]\sigma[/tex] and permeability is [tex]\mu[/tex]. 1st question is to find the surface current K and prove that vector potential [tex]A_{\phi}=\frac{B_0a^2}{2}\frac{r_{<}}{r_{>}^2}\sin\theta[/tex] in which [tex]r_{<}[/tex] and [tex]r_{>}[/tex] is the smaller (bigger) of r and a.

2. Relevant equations

[tex]\boldface{B}=\nabla X\boldface{A}[/tex]

3. The attempt at a solution

I can only find A using [tex]B=-1/2 rXA[/tex] inside the sphere but I didn't know the magnetic field outside. Or I have to use the example in the text to integrate the vector potential of a circular current loop from the bottom to top of the sphere?

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# Homework Help: Spherical coil

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