How does stroking an iron bar with a magnet turn it into a magnet? And why does dropping or heating a magnet destroy it?
The way this gets taught in class: an iron bar has hair.
Inside the bar are countless tiny norths and souths pointing in random directions. Because they point every which way they cancel each other out, and the bar has no magnetism. Stroke it in one direction with one pole of a magnet and they turn to line up – you are combing the hair. Once the hair is smooth and lying the same way, the bar is a magnet.
It also explains the destroying half of the syllabus in one move. Drop the magnet or heat it, and you mess the hair up again – which is exactly why a dropped or heated magnet loses its magnetism.
Nothing is physically pulled along the bar. The particles cannot move – they turn.
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