A thin walled spherical conducting shells `S` of radius `R` is given charge `Q`,the same amount of charge is also placed at its centre `C`.Which of the following statements are correct.

Options

A. On the outer surface of S. The charge density is `(Q)/(2piR^(2))`.
B. The electric field is zero at all points inside S.
C. At a point just outside S, the electric field is double the field is double the field at point just inside S.
D. At any point inside S, the electric field is inversley proportional to the square of its dentance from C.

Answer

A, C, D