A bar magnet is broken in half.Each half is broken in half again, etc.The observation is that each piece has both a north and south pole.This is usually explained by:

Question

Quizplus · Accepted Answer

Ampere's theory that all magnetic phenomena result from electric currents explains why each piece of a divided magnet still has both a north and south pole. This is because the atomic currents that produce the magnetic effects do not cease to exist upon division; instead, they continue to generate magnetic fields with both poles in each fragment.

A Bar Magnet Is Broken in Half