An insulating rod of length I carries a charge q distrubuted uniformly on it. The rod is pivoted at its mid-point and is rotated at a frequency f about a fixed axis perpendicular to the the rod and passing through the pivot . The magnetic moment of the rod system is

Options

A. `(piqfl^2)/12`
B. `(piqfl^2)/2`
C. `(piqfl^2)/6`
D. `(piqfl^2)/3`

Answer

D

Explanation

`M/L=q(2m)`
`=(q/(2m))(Iomega)=(q/(2m))((ml^2)/3) (2pif)=(piqfl^2)/3`