Hello, I am a bit trumped. I know how to calculate the voltage of a single uniform cylinder: V(r) = (-q/2 Pi ep0) Ln(r/R0) + V0 q: Charge density r: radius from outside of the cylinder. r >= R0 R0: radius of the uniform cylinder V0: applied voltage to the cylinder Here is my problem. How do I modal this given that I do not know the charge density. I will simply have a conducting cylinder with a voltage applied to it and no current will be flowing. This can be done for a sphere because I can use the capacitive formula of a sphere and substitute. But the cap. equation for a cylinder does not allow a single cylinder. Let me know.