Question

Surface charge density of a thin disc having radius R varies with distance from centre as σ=σ 0
​ r
R
​ (r 
​ =0) then total charge of disc is

Answer 1

Explanation:

The surface charge density of a thin charged disc of radius R is

. The value of the electric field at the centre of the disc is

. With respect to the field at the centre, the electric field along the axis at a distance R from the centre of the disc reduces by