## Surface currents

1. The problem statement, all variables and given/known data
If a uniform current with current density s flows around a tube of radius a-- so it is a surface current, how might I find the magnetic field at some arbitrary position vector r?*

2. Relevant equations

Biot-Savart?

3. The attempt at a solution

I am guessing Biot-Savart? Or is there a simpler way since it has nice symmetry?
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 Your geometry hasn't been described all that well, but why not ampere? $$\int \mathbf{B} \cdot d\mathbf{l}=\int \mathbf{J} \cdot d\mathbf{a}$$

 Tags electro magnetism