A uniform semicircular ring of radius R is in yz plane with its centre at the origin. The half ring carries a uniform linear charge density of `lamda`.
(a) Find the x, y and z component of Electric field at a point P(x, 0, 0) on the axis of the ring. (b) Prove that the field at P is directed along a line joining the centre of mass of the half ring to the point P.