Question

An electric field in a certain region is radially outwards from origin and has a magnitude equal to AP/ 2, where r is distance from the origin. The charge contained in a
sphere of radius R, centered around origin is

Answer 1

Answer:

Correct option is

A

4πϵ0Aa3

From Gauss's law,

∮E⋅dS=ϵ0qenc

At  r=a, E=Aa

∴∮E⋅dS=(Aa)4πa2=ϵ0qenc

⇒qenc=4πϵ0Aa3