Electrostatic Conformal Mapping Problem

[Airsteve0]

Homework Statement

The transformation z=\frac{1}{2}(w + \frac{1}{w}) maps the unit circle in the w-plane into the line −1≤x≤1 in the z-plane.

(a) Construct a complex potential in the w-plane which corresponds to a charged
metallic cylinder of unit radius having a potential Vo on its surface.

(b) Use the mapping to determine the complex potential in the z-plane. Show that
the physical potential takes the value Vo on the line −1≤x≤1. This line thus
represents a metallic strip in the x-y plane.

Homework Equations

F(w) = \Phi(u,v)+i\Psi(u,v) = \frac{-\lambda}{2\pi\epsilon_o}Ln(w) + Vo

x = \frac{1}{2}(u + \frac{u}{u^2 + v^2})

y = \frac{1}{2}(v - \frac{v}{u^2 + v^2})

The Attempt at a Solution

So far I have worked out the relation between (x,y) and (u,v) as well as made an attempt at part (a). However, it is part (b) and using the mapping that I am completely lost with. Mainly, if I try to find u and v in terms of solely x and y I get 2 solutions (i.e. plus or minus because of squaring); this leaves me unsure of what to do. Any help would be wonderful!

 

[marcusl]

Please do not double post. I have replied to the version in Homework/Advanced Physics.