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pentazoid
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Homework Statement
A rectangular loop of wire is situated so that one end (height h) is between the plates of a parallel plate capacitor, oriented parallel to the field E. The other end is way outside , where the field is essentially zero. What is the emf in the loop? If the total resistance is R, what current flows? Explain. [Warning: this is a trick question, so be careful if you have invented a perpetual motion , there's probably something wrong with it.
Homework Equations
V= -[tex]\int[/tex] E[tex]\bullet[/tex] dl
The Attempt at a Solution
E=[tex]\sigma[/tex]/[tex]\epsilon[/tex]0
[tex]\sigma[/tex]=Q/A
E=Q/(A*[tex]\epsilon[/tex]0), since each parallel plate capacitor is in the shape of a rectangle, A=hb
E=Q/(hb*[tex]\epsilon[/tex]0),
This question comes right out of Griffifth's E&M Textbook and the illustration of the capacitor is on p.294 if you have trouble picturing my description of the capacitor in your head.
I integrate over h and I get: EMF=Q*ln(h)/(b*[tex]\epsilon[/tex]0)
Bu the problem says that the field on one end of the parallel plate capicator is 0. Therefore the emf is zero, at least on that end of the capicator is zero.