Question

An insulating rod of length / carries a charge q
distributed uniformly on it. The rod is pivoted at its
one end and is rotated with angular velocity w
about a fixed axis perpendicular to rod and passing
through the pivot. The magnetic moment of system
is
​

Answer 1

πqFlsquare /6

Consider a small element at a distance xx of small width dx.dx.

Magnetic moment of the small element is-

dm=

(lqdx)ω/2π×πr2

Integrating from -1/2 to 1/2 give the final answer.