Finding the Electric Field for a Metal Ring in a Magnetic Field

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Homework Statement



A metal ring of radius a is located in a region with the homogenous magnetic flux density:

\hat{B} =\hat{z}B_0 cos(\omega t)

The metal ring coincides with the plane z=0. The frequency w is very low.

Use Faraday´s Law to determine the electric field where the metal ring is located

Homework Equations



Faraday´s Law

\nabla \times E= -\frac{dB}{dt}

The Attempt at a Solution

Cylindrical coordinates.

The Electric field is directed in the \varphi direction around the ring.Rotation of E then becomes:

-\frac{dE_{\varphi}}{dz}\hat{r} + \frac{1}{r} \frac{d(rE_{\varphi})}{dr}\hat{z} = \hat{z}B_0 \omega sin(\omega t)Is this a correct beginning, and how do i proceed from this point?
 
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It's admirable to start from the Maxwell relations explicitly. Most people probably would not.

hint: what is Faraday's law?
hint: what relates emf and electric field?

I'm actually looking at your approach, it should of course yield the same result, will be either fun or frustration for me.
 
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