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noblegas
Nov1-09, 10:22 PM
1. The problem statement, all variables and given/known data

A very long cylinder of liner dielectric materil is placed in an otherwise uniform electric field E_0 . Find the resulting field within the cylinder. (the radius is a , the susceptibililty \chi_e and the axis is perpendicular to E_0)

2. Relevant equations



3. The attempt at a solution

V_in(r,\theta)= \sigma(l=0..infinity)A_l*r^l*P_l(cos(\theta)

should I take the derivative of V_in with respect to r to obtain the field? Not sure why latex isn't display infiinity but l is supposed to range from zero to infinity

I also know that E_0 = \lambda/(2*\pi*\epsilon_0*a)

P_0=\epsilon_0*\chi_e*E_0 P=\epsilon*\chi_e*E ; should I plugged \chi_e=P/(E_0*\epsilon_0) into P to get E?

gabbagabbahey
Nov2-09, 05:46 PM
Why are you using the general solution of Laplace's equation in Spherical coordinates (with azimuthal symmetry), when cylindrical coordinates are more appropriate?

noblegas
Nov3-09, 12:16 PM
Why are you using the general solution of Laplace's equation in Spherical coordinates (with azimuthal symmetry), when cylindrical coordinates are more appropriate?

You are right. I just realized that. Is my approach to the problem correct? I should not necessarily assume that the length of a very long cylinder is approaching infinity?

gabbagabbahey
Nov3-09, 01:02 PM
I would assume that the cylinder is infinitely long....Are there any symmetries present (eg. axial, radial, azimuthal etc.)? What is the general solution to Laplace's equation in cylindrical coordinates with these symmetries?