$2 \ A$ current is flowing through two different small circular copper coils having radii in the ratio $1:2$. The ratio of their respective magnetic moments will be

What is the magnetic dipole moment for a coil? Write its $SI$ unit and dimensional formula,and explain its stable and unstable equilibrium.

$A$ steady current $i$ flows in a small square loop of wire of side $L$ in a horizontal plane. The loop is now folded about its middle such that half of it lies in a vertical plane. Let $\overrightarrow {{\mu _1}} $ and $\overrightarrow {{\mu _2}} $ respectively denote the magnetic moments due to the current loop before and after folding. Then

$A$ wire of length $L \ m$ carrying a current $I \ A$ is bent in the form of a circle. The magnitude of its magnetic moment is

$A$ circular coil of radius $10 \text{ cm}$ and $100$ turns carries a current of $1 \text{ A}$. What is the magnetic moment of the coil?

An electron in a circular orbit of radius $0.05 \ nm$ performs $10^{16}$ revolutions per second. The magnetic moment due to this rotation of the electron is (in $A \ m^{2}$):