A charged sphere of radius a has a spherically symmetric charge density ρ(r) = kr that varies linearly with the distance r from the center O. The total charge of the sphere is Q. This charged sphere is surrounded by a grounded conducting sphere of radius b > a that is also centered at O, as shown in the Figure. (1) Find the electric field E(r) everywhere in space. (2) Plot the magnitude of the electrostatic field as a function of the distance r from the center O. (3) Find the electrostatic potential everywhere in space. (4) Plot the magnitude of the electrostatic potential as a function of the distance r from the center O.
