Does this answer look right? (Infinitely long conductor pipe)

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Homework Statement



Fig. 1 shows the cross-section of an infinitely long conducting pipe. The inner radius of the pipe is r = R1, and the outer radius is r = R2. Suppose the inner surface has a constant voltage V = Vc > 0, and the outer surface has a constant voltage V = 0. The voltage distribution between the inner and outer surface (blue region) is governed by the Laplace's equation ∇2V=0 expressed in polar coordinates. Solve for V with the given boundary conditions.

[Note: Fig. 1 just looks like a blue annulus centered at the origin in the plane.]

Homework Equations



Don't worry about them for now.

The Attempt at a Solution



Just tell me whether my solution V = (Vc log(r) - log(R2))/(log(R1) - log(R2)) intuitively seems like it's correct. I don't want you to carry out the process of deriving this ... unless you want to.
 
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I.e. the voltage at a distance r from the center of the piper is proportional to log(r)
 
EDIT:

Actually I got

V(r,θ) = Vc * [log(r) - log(R2)] / [log(R1) - log(R2)].​

Does that seem right?
 
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