question_answer

The electric field due to a uniformly charged non-conducting sphere of radius R as a function of the distance from its centre if represented graphically by:

A)

B)

C)

D)

Correct Answer: B

Solution :

                Outside the spherical charge, the intensity of electric field at a point P situated at a distance r from the centre of the charge is  \[E=\frac{1}{4\pi {{\varepsilon }_{0}}}\,\,\frac{q}{{{r}^{2}}}\]                (if r > R) On the surface of spherical charge the electric field is given by      \[E=\frac{1}{4\pi {{\varepsilon }_{0}}}\,\,\frac{q}{{{r}^{2}}}\]              (if r=R) and inside the spherical charge the electric field: is. \[E=\frac{1}{4\pi {{\varepsilon }_{0}}}\,\,\frac{qr}{{{R}^{3}}}\] Hence, the variation of E-r is a follows: Note: At the centre of sphere, r = 0, so E = 0.