question_answer

A hollow metal sphere of radius R is uniformly charged. The electric field due to the sphere at a distance r from the centre:           [NEET 2019]

A) Zero as r increases for r < R, increases as r increases for r > R

B) Decreases as r increases for r < R and for r > R

C) Increases as r increases for r < R and for r > R

D) Zero as r increases for r < R, decreases as r increases for r > R

Correct Answer: D

Solution :

[d]

\[{{E}_{inside}}=0\]

\[{{E}_{surface}}=\frac{kQ}{{{R}^{2}}}=\max .\]

\[{{E}_{outside}}=\frac{kQ}{{{r}^{2}}}\]

\[E\propto \frac{1}{{{r}^{2}}}\]