In given hollow cylindrical conductor current density is $J = \frac{J_0}{r^2}$ where $J_0$ is constant and $r$ is the distance from axis of cylinder. If radius of inner surface is $'a'$ and radius of outer surface is $2a$ then find current passed through the conductor.
A$\pi J_0 ln2$
B$2\pi J_0 ln2$
C$2\pi J_0$
D$2\pi J_0 ln3$
Medium
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B$2\pi J_0 ln2$
b
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