Question

A bar magnet is cut in half. What happens to the magnetic properties of the two pieces, and why?



The two pieces repel each other because their fields reverse.


Each piece forms a new north and south pole because the domains realign in each section.


Both pieces become non-magnetic because the magnetic field is destroyed


Only the piece with the original north pole remains magnetic.

Answer 1

Each piece forms a new north and south pole because the domains realign in each section.

Explanation: magnetism in a bar magnet comes from aligned microscopic magnetic dipoles (domains). There are no isolated magnetic monopoles, so when you cut a magnet you do not get single poles — each piece must have both a north and a south. (In practice the cut faces become opposite poles, so the two halves will attract; only mechanical damage or heating during cutting can partially demagnetize them.)