Two wires of the same length are shaped into a square and a circle. If they carry the same current,the ratio of their magnetic moments is:

The magnetic moment vectors $\mu_{s}$ and $\mu_{l}$ associated with the intrinsic spin angular momentum $S$ and orbital angular momentum $L$ respectively,of an electron are predicted by quantum theory (and verified experimentally to a high accuracy) to be given by $\mu_{s} = -(e/m)S$ and $\mu_{l} = -(e/2m)L$. Which of these relations is in accordance with the result expected classically? Outline the derivation of the classical result.

The relation between magnetic moment $(M)$ of a current-carrying circular coil and the length $(L)$ of the wire used is:

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

$A$ ring of radius $R$,made of an insulating material,carries a charge $Q$ uniformly distributed on it. If the ring rotates about the axis passing through its centre and normal to the plane of the ring with a constant angular speed $\omega$,then the magnitude of the magnetic moment of the ring is:

$A$ wire of length $314 \, cm$ carrying a current of $14 \, A$ is bent to form a circle. The magnetic moment of the coil is $........ \, A \cdot m^2$. [Given $\pi = 3.14$]