The electrostatic potential inside a charged spherical ball is given by = ^2+b where r is the distance from the centre; a, b are constants. Then the charge density inside ball is

Step-by-step solution

Potential inside ( )=a r^2+b E _ r =- v r =-2 ar Electric field inside uniformly charged solid volume varies with ' r '. So charge density is constant aligned & _ net =(-2 ar ) 4 r ^2=-8 a r^3 & -8 ar ^3= 4 3 r ^3 ₀ & =-6 a ₀ aligned