Homework Help: Electric potential of concentr

Electric potential of cylindrical conductor placed in a cylindrical conducting shell

1. The problem statement, all variables and given/known data




A cylindrical conducting shell is placed concentric with a cylindrical conductor. Assume that a total charge density λ0 = 2.60 µC/ m is placed on the inner cylinder and a total charge density λ = -2.90 µC/ m is placed on the outer one, r0 = 8.40 cm, r1 = 16.80 cm and r2 = 21.00 cm. Calculate, relative to r = 10·r0 = 84.0 cm:

[1pt] the electric potential at r = 30.80 cm.


Answer: -5.41E+03 V
(I need help figuring out HOW to get this answer, not the answer itself)




2. Relevant equations


V= the negative inegral of E
λ=Q/2(pi)r


3. The attempt at a solution

So far all I've done is that I've integrated E=2kλ/r and got v=(-2kλ)ln(r)+C for the conducting shell and Vo=(-2kλo)ln(ro)+C for the conductor.

I'm not really sure what to do with the question, though.

I'm thinking I could use those equations to find the potential of both the cylindrical conductor and the cylindrical conducting shell. Then what?

And for the shell, would I have to use the two radiuses to find it on the outside of the shell and the inside too? I have no idea, I need assistance haha.

Help would be appreciated.

 

okay, I'll give it a shot, thanks!