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 5-5-2019]

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 :

\[{{E}_{inside}}=0\] \[{{E}_{surface}}=\frac{kQ}{{{R}^{2}}}=\max .\] \[{{E}_{outside}}=\frac{kQ}{{{r}^{2}}}\] \[E\propto \frac{1}{{{r}^{2}}}\]