The magnitude of the repulsive force between two point charges with the same sign, one of size 1 and the other of size q, is F = q/4πε0r2 where is the distance between the charges and ε0 is a constant. The potential V at a point P due to the charge is defined to be the work expended in bringing a unit charge to P from infinity along the straight line that joins and . Find a formula for V.