A conducting sphere of radius R at potential zero is surrounded by a concentric
ID: 1914448 • Letter: A
Question
A conducting sphere of radius R at potential zero is surrounded by a concentric spherical shell of dielectric material of inner radius R, outer radius 2R, and dielectric constant ?=7/5. Suppose that the sphere and the dielectric shell are placed in an initially uniform electric field E0 in the z direction.
Show that the potential is given by:
?(r,?)=-E0rcos? + (2E0R3/r2 )cos? for r?2R
?(r,?)=-(6/7)E0(r - R3/r2)cos? for R?r?2R
I have this problem mostly solved, but I still need to know where the 2 in the first equation comes from.
It should be (?2