Let $\rho (r)\, = \frac{Q}{{\pi {R^4}}}\,r$ be the volume charge density distribution for a solid sphere of radius $R$ and total charge $Q$. For a point $'p'$ inside the sphere at distance $r_1$ from the centre of the sphere, the magnitude of electric field is

  • A

    $0$

  • B

    $\frac{Q}{{4\pi {\varepsilon _0}r_1^2}}\,$

  • C

    $\frac{{Q{r_1}}}{{4\pi {\varepsilon _0}{r^4}}}\,$

  • D

    $\frac{{Qr_{_1}^2}}{{4\pi {\varepsilon _0}{R^4}}}\,$

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 List-$I$  List-$II$
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  • [IIT 2018]