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Example: Separation of variables in spherical coordinates. A specified charge density s 0 (q) is glued over the surface of a spherical shell of radius R. Find the resulting potential inside and outside the sphere. z. s 0 (q). q. region 2. region 1.
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Example: Separation of variables in spherical coordinates A specified charge density s0(q) is glued over the surface of a spherical shell of radius R. Find the resulting potential inside and outside the sphere. z s0(q) q region 2 region 1 Since the potential is continuous ar r=R:
Now, let us multiply both sides by Pl(cosq) and utilize the relation: where
Let us consider the distribution: This yields The potential inside the sphere (region 1) is: while the potential outside the sphere (region 2) is: Example: A spherical surface of radius R has the charge uniformly distributed over its surface with a density Q/4pR2, except for a spherical cap at the north pole, defined by the cone q=a. . Find the resulting potential inside and outside the sphere. Hint: use the identity Remember:
Dipole Moment +q -q For dipole moment