$2 \ A$ 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

$A$ current of $3 \, A$ is flowing in a plane circular coil of radius $4 \, cm$ and number of turns $20$. The coil is placed in a uniform magnetic field of magnetic induction $0.5 \, T$. The magnetic dipole moment of the coil is $... \, A \cdot m^2$.

$A$ current-carrying circular loop is freely suspended by a long thread. The plane of the loop will point in the direction:

$A$ circular loop having radius $r$,carrying current $I$,produces a magnetic field at the centre of the loop equal to $B$. What will be the magnetic dipole moment of this loop?

$A$ circular coil of radius $4\, cm$ and of $20$ turns carries a current of $3$ amperes. It is placed in a magnetic field of intensity $0.5\, Wb/m^2$. The magnetic dipole moment of the coil is.......$A \cdot m^2$.

$A$ particle of mass $m$ and charge $Q$ moving with a speed $v$ in a circular path of radius $R$ has a magnetic moment $\mu$. If the mass of the particle is doubled and it maintains the same speed while revolving in the same circular path,then the magnetic moment will be