A total charge Q is uniformly distributed around a ring-shaped conductor with radius α. A charge q is located at a distance x from the center of the ring (Figure). The force exerted on the charge by the ring is given by
F = 1/4πe0 qQx/(x2 + α2)3/2
Where e0 = 8.85 x 10-12 C2/(N m2), q = Q = 2 x 10-5 C, and α = 0.9 m. Determine the distance x where the force is a maximum.