Problem 6. Calculate the amount of electrostatic energy of a uniform sphere of charge in vacuum with radius b and volume charge density stored in the following regions:
Hint: use,
We = E^2 * dU (J).
(a) Inside the sphere
(b) Outside the sphere
(c) Calculate the total electrostatic energy to assemble this uniform sphere, by calculating
W = dW = [v * dq], where v is an intermediate scalar potential when dq is assembled.
Hint: Discretize the sphere into a sum of thin spherical shells of thickness dR, then integrate.
(d) Compare the results of (a), (b), and (c) and find the relation between them.