# The electrostatic potential inside a charged spherical ball is given by

Question:

The electrostatic potential inside a charged spherical ball is given by $\phi=a^{2}+b$ where $r$ is the distance from the centre; $a, b$ are constant. Then the charge density inside the ball is :-

1. $-24 \pi \mathrm{a} \in_{0}$

2. $-6 a \in_{0}$

3. $-24 \pi a \in_{0} r$

4. $-6 a \in_{0} r$

Correct Option: , 2

Solution: