Charge is distributed within...|Electrostatics|JEEMAIN 2019

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JEE MAIN 2019

09-01-19 S2

Question

Charge is distributed within a sphere of radius $R$ with volume charge density $\rho(r)=\frac{A}{r^2} e^{\frac{-2 r}{a}}$, where $A$ and a are constants. If $Q$ is the total charge of this charge distribution, the radius R is:

Select the correct option:

A

$\frac{a}{2} \log \left(\frac{1}{1-\frac{Q}{2 \pi a A}}\right)$

B

$\frac{\mathrm{a}}{2} \log \left(\frac{1}{2 \pi \mathrm{aA}}\right)$

C

$a \log \left(1-\frac{Q}{2 \pi a A}\right)$

D

$a \log \left(\frac{1}{1-\frac{Q}{2 \pi a A}}\right)$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

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