I'm revising for my exam and got stuck in the following questions. Please help. 1) An isolated spherical conductor of radius r is charged to a potential V. The total electrical energy stored is _______. This is an MC question and the answer is V2(2*pi*εo*r) I only know energy stored = Qq/(4*pi*εo*r) and V=Q/(4*pi*εo*r) 2)A positively-charged metal sphere A of radius a is joined by a conducting wire to an uncharged metal sphere B of radius b placed far away from the first sphere. THe ratio of the surface charged density on sphere A to that on sphere B is ______. The answer is b/a. Well, I know surface area of A :surface area of B = a^2:b^2. How can I get the answer b/a ? Thanks in advance.