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

A very thin disk of non-conducting material initially holds a charge Q_{O}= +5 μC that decreases with time t as

Q(t) = Q_{O}e^{-t/τ}

where τ = 10 seconds.

If the disk has a radius of 0.10 m, what is the magnitude and direction of the magnetic field at the circumference of the disk as a function of time?

2. Relevant equations

Assume at any time t that the displacement vector D is uniform across the disk.

There is no free current.

∇[itex]\bullet[/itex]E = (1/ε_{O})ρ

∇×B = μ_{O}J + μ_{O}ε_{O}(∂E/∂t)

3. The attempt at a solution

I tried to just work out the curl of B and I immediately ran into problems and it's not correlating to the problem.

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# Homework Help: Magnitude and Direction of a Magnetic Field at the Circumference of a Disk

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