What is the electric field intensity at the centre of the uniformly charged non-conducting sphere?

Q. At what conditions, is the electric field intensity due to a uniformly charged non-conducting sphere zero?

Q. Calculate electric field intensity due to uniformly charged non-conducting sphere:
(a) outside the sphere
(b) at the surface of sphere
(c)inside the sphere
(d) at the centre of the sphere
Plot at graph between electric Held intensity and distance.

Q. Intensity of electric field inside a uniformly charged conducting hollow sphere is :

Q. Select the correct alternative : A non-conducting solid sphere of $R$ is uniformly charged. The magitude of the electric field due to the sphere at a distance $r$ from its centre: