Question

apply gauss's theorem to show that for a spherical shell, the electric field inside the shell vanishesh, where as outside it. the field is as if all the charge had been concentrated at the centre?​

Answer 1

draw a spherical shell of radius r and all the charge is concentrated on the surface of the shell

let's find out electric field at the surface of shell

consider a spherical gaussian surface of radius r

and apply gauss theorem

E=q/4 pi epsilon r^2

as the charge is concentrated at the center of the sphere