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

Question 3 of http://www.damtp.cam.ac.uk/user/examples/B10b.pdf .

2. Relevant equations

[itex]\nabla \times B = \mu_0 J[/itex]

3. The attempt at a solution

I know for a cylinder, J (vector) = J (scalar) * k (vector), where unit k is the vector in the z-direction. So [itex]\nabla \times B = (0, 0, \mu_0 J)[/itex], somewhere (not quite sure where this is true in terms of a, b, d). I think I need to find B for the big cylinder, then B for the small cylinder, and combine them somehow? I don't see why the field in between the cylinders is important; we're only interested in B for x² + y² < a².

Thanks!

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# Homework Help: Steady Current and Magnetic Field

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