The surface charge density of a thin charged disc of radius R is ρ . The value of the electric field at the centre of the disc is 2ϵ0ρ . With respect to the field at the centre, the electric field along the axis at a distance R from the centre of the disc:
a. reduces by 70.7%
b. reduces by 29.3%
c. reduces by 9.7%
d. reduces by 14.6%