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

Answer

$2$

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