A solid metallic sphere of radius a carries total charge Q. No other charges are nearby. The electric field just outside its surface is kQ/a^2 radially outward. At this close point the uniformly charged surface of the sphere looks exactly like a uniform flat sheet of charge.Is the electric field here given by σ/ε or σ/2ε?
how come it is not σ/2ε since it is a sheet of charge?