In which direction does a free hanging magnet get stabilized ? Explain.

A magnetic needle is kept in a non-uniform magnetic field. It experiences

The $ S.I.$  unit of magnetic permeability is

Write the equation of magnetic field on the axis of current carrying finite solenoid.

Two small bar magnets are placed in a line with like poles facing each other at a certain distance $d$  apart. If the length of each magnet is negligible as compared to $ d,$  the force between them will be inversely proportional to

A bar magnet of length $'l'$ and magnetic dipole moment $'M'$ is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be