Question

The magnitude of electric field due to point charge $2q$, at distance $r$ is $E$. Then the magnitude of electric field due to a uniformly charged thin spherical shell of radius R with total charge q at distance $\frac{r}{2}(r>>R)$ will be

Answer 1

Field due to point charge
$\frac{2q}{4\pi {\epsilon }_0\times r^2}=E$

Field due to shell at point outside, $E_2=\frac{q}{4\pi {\epsilon }_0\times \left(\frac{r^2}{4}\right)}$

$\therefore \frac{R_2}{E}=\frac{2}{1}$

$\Rightarrow E_2=2E$