MCQ
Graphical variation of electric field due to a uniformly charged insulating solid sphere of radius $R$, with distance $r$ from the centre $O$ is represented by:

  • B

  • C

  • D

Answer

Correct option: A.

a
Electric field of solid sphere (uniformly charged)

$E( r ) \begin{cases}\frac{ Q }{4 \pi \in_0 r ^2} & r \geq R \\ \frac{ Qr }{4 \pi \in_0 R ^3} & r \leq R \end{cases}$

Graphically

$E(r) \propto r$ for $r \leq R$

$\propto \frac{1}{r^2} \text { for } r \geq R$

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