MCQ
A Solid sphare of radius $R$ has a charge $Q$ distributed in its Volume with a charge density $P=K r^a$ Where $K$ and a are constants and $r$ is the distance from its centre from its centre. if the electric filed at $r=\frac{R}{2}$ is $\frac{1}{8}$ times that at $r=R$, the value of $a$ is.
- A$3$
- B$5$
- ✓$2$
- D$7$
