An insulating, thin rod of length l has... | Magnetic Effects of Current

JEE Main 2019

10-01-2019 S1

Question

An insulating, thin rod of length I has a linear charge density $\rho(x)=\rho_0 \frac{x}{I}$ on it. The rod is rotated about an axis passing through the origin $(x=0)$ and perpendicular to the rod. If the rod makes $n$ rotations per second, then the time averaged magnetic moment of the rod is

Select the correct option:

$\pi \mathrm{n} \rho \ell^3$

$n \rho \ell^3$

$\frac{\pi}{4} n \rho \ell^3$

$\frac{\pi}{3} n \rho \ell^3$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution