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

there is a cylindrical area in xy plane with a magnetic field (into the plane) that changes with time like that: (dB/dt)=δ

the magnetic field outside the area is 0. the radius of the cylinder is a.

we pick a string in the circle with lentgh L which is smaller than the diameter(2a). let's call the points that connect the string - A and B.

I have to find the emf between those points.

its looks like that:

http://img714.imageshack.us/img714/7092/emfk.jpg [Broken]

the answer is -(Lδ/2)√[(a^2)-(L/2)^2]

please show me how can I get it. thanks

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# Homework Help: The emf of a string in a circle - magnetic fields

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