If the size of a magnet does not determin its strength, then what physical property does? THANX
do you mean a ferromagnet or electromagnet?
a ferromagnets strenght is determined by the material. Simplified, the more unpaired electrons in the material the stronger magnetic field it has. The atoms has to be fairly alinged aswell so the magnetic dipol moments add up instead of cancel eachother.
Offcourse if you have 2 magnets of the same material the bigger magnet will be the stronger.
Here is a link I think you will find interesting
A electromagnets strenght is determined by the current you run through it.
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