Does the length of an iron bar change when it is magnetized?

When magnetised, length of an iron bar

When magnetised, length of an iron bar

An iron bar is magnetised with the help of another magnet or by subjecting it to a magnetising field. The magnetism acquired by the magnet is assumed due to the alignment of molecular magnet. Does the length to the iron bar undergo a change during the magnetisation process?

Magnetic length of a bar magnet is

Magnetic length of a bar magnet is

In double touch method of magnetization what is the polarity of the end of an iron bar at which the magnetizing magnet leaves ?

What will be the change in the length of each small bar magnet when a bigger bar magnet is cut into 4 equal parts parallel to the equatorial line ?