Assertion : The poles of magnet can not be separated by breaking into two pieces.

Reason : The magnetic moment will be reduced to half when a magnet is broken into two equal pieces.

Two lines of force due to a bar magnet

A short bar magnet with its north pole facing north forms a neutral point at $P$ in the horizontal plane. If the magnet is rotated by $90^o$ in the horizontal plane, the net magnetic induction at $P$ is (Horizontal component of earth’s magnetic field = ${B_H}$)

In two separate experiments the neutral points due to two small magnets are at a distance of $r$ and $ 2r$ n broad side-on position. The ratio of their magnetic moments will be

A magnet is placed in iron powder and then taken out, then maximum iron powder is at