The magnetic moment of an electron moving in a circular orbit of radius $R$ with a time period $T$ is

Two thick wires and two thin wires,all of the same material and same length,form a square in three different ways $P, Q,$ and $R$ as shown in the figure with the current connection indicated. The magnetic field at the centre of the square is zero in cases:

$A$ uniformly charged dielectric ring rotating with constant angular velocity $\omega$ about its geometrical axis produces:

In the given diagram,a rod is rotating with angular velocity $\omega$. The mass of this rod is $m$,the charge is $q$,and the length is $l$. Find the magnetic moment of this rod.

Write the formula for the magnetic field due to a current-carrying loop acting as a magnetic dipole at a point on its axis,and compare it with the formula for the electric field of an electric dipole.

An electron of charge $e$ moves in a circular orbit of radius $r$ around the nucleus at a frequency $v$. The magnetic moment associated with the orbital motion of the electron is