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

suppose we have a coil sitting on a desk (with radius =1), and then a spark passes by the side of it, in such a way that the magnetic flux through the coil is maximized. The coil is attached to a full wave rectifier which is connected to a very large capacitor.

There is an initial potential difference of 1.94MV, which causes the air to break down and creates a 2m long spark.

Find the average V and maximum V in the coil during dielectric breakdown

How much power can the coil produce from the spark?

2. Relevant equations

B(R,t)[itex]\approx\frac{\mu_{0}I(t)}{2\pi R}[/itex] (in the region of the coil)

[itex]\Phi_{B}(t)=\oint B(R,t) \bullet ds[/itex]

V(t)=N[itex]\frac{d\Phi_{B}(t)}{dt}[/itex]

3. The attempt at a solution

I know that the V in the coil depends on [itex]\frac{d\Phi_{B}}{dt}[/itex]

and B depends on the current, but since this is a spark, I don't know how to say what the current is...

I think [itex]\frac{d\Phi_{B}}{dt}[/itex] will be very large since the time is almost instantaneous, but I have no idea how to handle a spark as a current.

This is not for class, but just to satisfy my curiosity

any help would be greatly appreciated!

thanks!

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# Homework Help: Emf / coil induction from a spark

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