A point charge q is situated a distance a from the center of a conducting sphere of radius R. The sphere is not grounded. Using the method of images, calculate the potential outside the sphere in two different cases: (a) The sphere is neutral and kept at a constant potential V0.
(b) The sphere has total charge Q.
Hint: you will need to add a second image charge besides the one we included in class to solve the problem of the grounded sphere.