Electrostatic Potential of cylindrical surface

greygasher
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Homework Statement


The figure shows a section of a cylindrical surface, height h and radius R. The curved surface extends from the z-axis to the y-axis only and has a charge density given by σ(z)= σ0z where σ0is some constant. ind the electrostatic potental at a. (a is at the origin)

I'm sorry I'm not sure how to get the picture up here. It's not that complicated, just a cylindrical shell but it's cut in a way that nothing cancels out (as I hope is obvious from the problem description)

Homework Equations


(1) Laplace/Poisson

or

(2)
690ab6aada2735237ee2fba30dc1698b.png


The Attempt at a Solution


I'm really kind of at a loss. I could solve the Laplace for cylindrical coordinates (as that is where our lectures have been heading) but I feel like there's absolutely no symmetry to exploit and it would be way too much work. I would almost just want to find the electric field and integrate to get the potential, but we've never really done (nor can I find much help online with) a varying charge density. So I get stuck with finding the enclosed charge.
If I end up needing to use Laplace, I'd like some help with my boundary conditions and probably making sense of the whole mess. I can follow the derivation alright but the solution is a hair away from being over my head.
 
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what about integrating the charge density over the area.
<br /> V(r)= \int_{a}^{b}\frac{\sigma}{4\pi\epsilon_0r}da<br />
 
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