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

There's a capacitor with circular plates of radius 50 mm and separated by a distance of 5 mm. We apply a sinusoidal difference of potential whose maximum value is 150 V and has a frequency of 60 Hz. Determine the amplitude of the magnetic field, between the plates and at a distance of 50 mm away from the center of the capacitor.

2. Relevant equations

I've no idea.

3. The attempt at a solution

I've no clue about what equation to use. I'm thinking about Maxwell's equation: [tex]\oint \vec B d\vec s =\mu _0 \varepsilon _0 \frac{d\Phi _E}{dt}+\mu _0 I_{\text{enclosed}}[/tex] but I'm not even sure.

In any case, I'm almost sure I have to calculate the E field of such a capacitor. I don't know if this is right, but I reached that the E field in a point situated inside the capacitor and over the straight line passing by both center of the plates as to be worth [tex]4\pi d \sigma \int _0 ^{0.005} \frac{dr}{r^2 \sqrt{r^2+d^2}}[/tex] and I'm stuck here.

But I'm not sure this is relevant to calculate the E field only in this line.

I've also figured out that [tex]V(t)=150 \sin (60 t)[/tex] and that [tex]\vec E =-\nabla V[/tex].

Any tip is greatly appreciated as I'm at a loss.

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# Homework Help: Capacitor+magnetic field

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