A bar magnet is cut into two pieces A and B, from the middle, as shown in the figure.

Will the two pieces act as individual magnets? Mark the poles of these two pieces. What will happen if these magnets are further broken?

Yes, the two pieces act as individual magnets. The poles of two pieces of magnet are:

The magnetic poles always exist in pairs. When an attempt is made to separate the magnetic poles by breaking a bar magnet in the middle, then it is observed that each of the two parts forms a complete magnet. New magnetic poles are developed at broken ends. Now if we further break each of these parts into two, even then each part will be a complete magnet and will contain a north pole and a south pole. Thus, even if a magnet is broken into atoms, each atom will be a complete magnet. This clearly indicates that an isolated magnetic pole does not exist, i.e., each magnet is a dipole.