Two points $A$ and $B$ are situated at a distance $x$ and $2x$ respectively from the nearer pole of a magnet $2 \ cm$ long. The ratio of the magnetic field at $A$ and $B$ is

Describe the magnetic field lines of a bar magnet.

$A$ short bar magnet has a magnetic moment of $0.48 \; J \; T^{-1}$. Give the direction and magnitude of the magnetic field produced by the magnet at a distance of $10 \; cm$ from the centre of the magnet on
$(a)$ the axis,
$(b)$ the equatorial lines (normal bisector) of the magnet.

If two identical bar magnets, each of length $l$, pole strength $m$ and magnetic moment $M$ are placed perpendicular to each other with their unlike poles in contact, the magnetic moment of the combination is

If a bar magnet of pole strength $m$ and magnetic moment $M$ is cut equally $5$ times parallel to its axis and again $3$ times perpendicular to its axis, then the pole strength and magnetic moment of each piece are respectively

The force between two identical bar magnets whose centres are $r \ m$ apart is $4.8 \ N$,when their axes are in the same line. If the separation is increased to $2r$,the force between them is reduced to . . . . . . $N$.