5.(5pts) (calculus problem.) A metal ring, of Radius R, has a total charge +Q distributed uniformly on it. (2 = Q/2xR Coul/meter)). We found that the magnitude of the electric field, E(x), at a distance x on the line from the ring center is E(x) = k_Ox = kQ x (x2 + R2 )-3/2 (see Hint) (x2 + R2 )3/2 Note that E(0)=0 and E goes to zero for large value of x. Also E(x) 2 0 for all x. Thus, find the point, Xm , at which E(Xm) is a maximum of E(x) Hint: the derivative of a product dg(x)h(x)/dx= g(dh/dx) + h(dg/dx). +Q R E(Xm) Xm X X=0