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Can someone help?

I have 2 concentric cylinders which are both conductors. The inner conductor has linear charge density of 6 n C/m. The outer conductor has no net charge. The inner conductor has R of 0.015m, the distance between the inner conductor and the inner wall of the outer conductor is 0.03m, and the outer conductor has a radius of 0.065 m. I am to find the E field at all Rs.

So within the inner conductor, the R = 0.

outside the inner conductor but before you reach the inner wall of the outer conductor, the R is E*2*pi*R*L = 6e-9 * L/epsilon. So you simply that and you get 108/epsilon.

IN between the inner and outer wall of the outer conductor the E field is again 0.

But what about the E field outside the outer conductor? I know that it has to do with the ratio of the density, but I am not sure what I am doing wrong but I get the wrong answer when I say that the outer density is proportional to the radius ( = 6 * 0.065/0.015)? Any help would be great. THank you.

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# Homework Help: Concentric cylinders E field

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