According to section E3.4, the electric field E between two parallel plates with opposite, uniformly distributed charges is ( as long as the plates are very large compared to their seperation d) nearly uniform and has magnitude E= 4(pi)k(sigma), where sigma is the charge per unit area on the plates. Use this result to verify the equation included as an attachment.
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k = 1/4p e0
We have, E = 4pk s , where s is the surface charge density
or E = 4p [1/4p e0] s , value of k is substituted
E = [1/e0] s ...
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