Q7. (Electric field due to continuous charge distribution) A semi-circular ring lying in the y−z plane has a charge density ρl = ρ0 cosθ' coul /m, where θ′ is the angle measured from the z-axis as shown in the figure. (a) Find E for points (x, 0, 0) along the x-axis. (b) Show that for x ≫ R, the electric field is like that of a dipole, i. e. , depends on the cube (x3) of the displacement from the charge distribution.