Inside a bar magnet,the magnetic lines of force

$A$ bar magnet of magnetic moment $3.0 \, A-m^2$ is placed in a uniform magnetic induction field of $2 \times 10^{-5} \, T$. If each pole of the magnet experiences a force of $6 \times 10^{-4} \, N$,the length of the magnet is.....$m$

In the case of a bar magnet,lines of magnetic induction:

$A$ bar magnet of magnetic moment $M$ is placed at right angles to a magnetic induction $B$. If a force $F$ is experienced by each pole of the magnet,the length of the magnet will be

Two short magnets of equal dipole moments $M$ are fastened perpendicularly at their centres. The magnitude of the magnetic field at a distance $d$ from the centre on the bisector of the right angle is ($\mu_0 =$ Permeability of free space).

Three identical bar magnets are riveted together at the centre in the same plane as shown in the figure. This system is placed at rest in a slowly varying magnetic field. It is found that the system of magnets does not show any motion. The north-south poles of one magnet are shown in the figure. Determine the poles of the remaining two.