Electric Field in and outside a cylinder

AI Thread Summary
The discussion focuses on calculating the electric field (E) inside and outside an infinitely long cylinder with charge density lambda and radius R. For r < R, the electric field is determined using Gauss' law, where the flux equals the enclosed charge divided by epsilon. For r > R, the electric field can be expressed using the formula E = (lambda) / (2 pi epsilon not * r). Participants emphasize the importance of applying Gauss' law correctly and encourage sharing specific confusion or previous attempts at solving the problem. The conversation highlights the need for a clear understanding of electric field concepts in relation to cylindrical charge distributions.
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An infinitely long cylinder has charge density lamda and has a radius R.

What is E when r < R and when r > R.

I know the formula for an infinite line of charge is
E = (lamda) / (2 pi epsilon not * r)

Thanks!
 
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reising1 said:
An infinitely long cylinder has charge density lamda and has a radius R.

What is E when r < R and when r > R.

I know the formula for an infinite line of charge is
E = (lamda) / (2 pi epsilon not * r)

Thanks!

do you know Gauss' law?
 
Yes. Flux = q enclosed / Epislon
 
reising1 said:
Yes. Flux = q enclosed / Epislon

Hah. Well, have you tried to apply Gauss' law to this problem? The forum rules forbid posters from doing your homework for you. Instead, we are here to guide you. You won't get any help without posting the source of your confusion or posting work.

"here is the problem, thanks" is not acceptable
 
Okay well I know that the integral of E dotted with dA is the flux, which can be simplifed to EA due to the symmetry of the problem. And the area would be equivlant to the pi r squared times length. And q enclosed would be lamda times L.
 

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