Potential of a Charged Cylinder

AI Thread Summary
The discussion revolves around calculating the electric potential V0 of a hollow cylinder with a uniform surface charge as its height h approaches zero. Participants clarify that as h decreases, the cylinder effectively becomes a circular charge distribution. There is a need to determine the reference point for measuring potential, which could be at the surface or along the z-axis. The use of L'Hôpital's rule is suggested to resolve the limit mathematically. The conversation emphasizes the importance of defining the measurement point for accurate potential calculation.
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Homework Statement



A hollow cylinder of radius r and height h has a total charge q uniformly distributed over its surface. The axis of the cylinder coincides with the z axis, and the cylinder is centered at the origin, as shown in the figure.

21165_a.jpg


What is the potential V0 in the limit as h goes to zero?

Express your answer in terms of q, r, and ε0.

Homework Equations



http://photo.ringo.com/240/240690564O546905961.jpg

The Attempt at a Solution



with h=0, the values under the root would be 1 (1+0), and the other values in the parenthesis would be zero, so we would have ln(1) which is 0, and then 0 multiplied times the rest would also be 0, but this is incorrect.

Thanks in advance for the help!
 

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Where is Vo to be measured? On the surface I assume? And as h goes to zero, this becomes simply a circular charge distribution, doesn't it?
 
to perform that limit use l'hospitals rule from calculus. and like the previous states you need a reference point to calculate potential is it in the center or is it along the z axis
 
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