MCQ
Charge is distributed within a sphere of radius $R$ with a volume charge density $\rho (r) = \frac{A}{{{r^2}}}{e^{ - 2r/a}}$ where $A$ and $a$ are constants. If $Q$ is the total charge of this charge distribution, the radius $R$ is.
- A$a\,\log \,\left( {1 - \frac{Q}{{2\pi aA}}} \right)$
- ✓$\frac{a}{2}\,\log \,\left( {\frac{1}{{1 - \frac{Q}{{2\pi aA}}}}} \right)$
- C$a\,\log \,\left( {\frac{1}{{1 - \frac{Q}{{2\pi aA}}}}} \right)$
- D$\frac{a}{2}\,\log \left( {1 - \frac{1}{{2\pi aA}}} \right)\,$
