$A$ magnetized steel wire of length $L$ has a magnetic moment $M$. It is then bent into a semicircular arc. The new magnetic moment is:

$A$ permanent magnet:

$A$ wire of magnetic moment $M$ is bent to form a circular arc which subtends an angle $90^o$ at the center. Then,its new magnetic moment is:

$A$ long magnet is cut into two parts in such a way that the ratio of their lengths is $2 : 1$. The ratio of the pole strengths of both the sections is

Verify Ampere's law for the magnetic field of a point dipole with dipole moment $\vec{M} = M\hat{k}$. Take $C$ as the closed curve running clockwise along the $x$-axis from $x = R$ to $x = a$,then along a circular arc of radius $r$ in the $xz$-plane from $\theta = 0$ to $\theta = \pi$,and finally back to the starting point.

$A$ magnetized wire of magnetic moment $M$ and length $l$ is bent in the form of a semicircle of radius $r$. Then its new magnetic moment is: