Question

Can I use method of images for a point charge outside a solid dielectric sphere?

Answer 1

Find a potential at all points in space for a point charge q located in a free space a distance d from the center of a solid dielectric sphere of radius a(a<d) and dielectric constant ϵϵ0.

Answer 2

The solution of this problem is compared with the solution by separation of variables. The problem of a plane boundary between different dielectrics and a point charge is simply solved by the image method[1–7]. ... However, it is not wise to usea single dielectric when a problem involves multiple dielectricboundaries.

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