Potential at all points due to uniformly charged infinite cylinder

AI Thread Summary
The discussion revolves around calculating the electric potential around an infinitely long cylinder with uniform charge density. The standard approach involves using the equation V(a) - V(b) = -∫ba E(r')°dr' but poses challenges due to the divergence of potential at infinity. The participant suggests using an arbitrary reference point instead of infinity to avoid this issue. Clarification is sought on whether this method is acceptable and if additional steps are needed due to the non-zero reference point. The response emphasizes the importance of showing work in such calculations.
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Homework Statement


Infinitely long cylinder of radius R with uniform charge ρ. Calculate the electric potential at all points in space.


Homework Equations



V(a)-V(b)=-∫ba\vec{E}(\vec{r}')°dr'\hat{r}

The Attempt at a Solution



Generally potential is calculated with a reference point at r=∞ but in the case of an infinite cylinder I believe the integral above would diverge because the potential at ∞ (V(∞)) would not necessarily equal zero. What I did then is simply provide an arbitrary r' vector as the reference point and went through the problem as one would normally do so with a non-infinite charged object. Is this okay? Do I have to do something extra because of the non-zero reference point?

Thank you!
 
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It is right, but better to show your work.

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