Question

A conductive spherical shell with no load, of mass m floats with a third of its volume immersed in a dielectric liquid of dielectric constant ε. To what potential should the sphere be loaded so that it floats submerged halfway? Assume that the electric field of the charged sphere submerged halfway is purely radial and then show that the sum of the charges σ + σp on the spherical surface is such that this assumption is justified.

Answer 1