A spherical capacitor consists of two concentric spherical metal shells and has a radius a for the outer sphere and b for the inner sphere.
(i) Calculate the capacitance.
(ii) For a given value of a, what radius b should be chosen so that the conductor is able to store the greatest amount of electrical energy with the constraint that the electric field strength at the surface of the inner sphere may not exceed some value E0?
(iii) How much energy can be stored in this case?