How does magnetism arise in permanent magnets?

AI Thread Summary
Magnetism in permanent magnets arises from the alignment of individual electron magnetic moments within the material. Unlike moving charges that create magnetic fields through special relativity, permanent magnets generate their fields from stationary electrons in specific configurations. The magnetic properties depend on the arrangement of these moments, which can be grouped into domains that align in the same direction. When these domains align, they produce a significant overall magnetic field. Understanding this alignment is crucial for grasping the nature of magnetism in solid materials.
FredMadison
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Hi everyone!

As I understand it, magnetism can be explained by special relativity when charges are moving - length contraction in different frames of reference leads to coulomb forces between the charges in these frames.

But how does magnetism in a permanent magnet arise? Are there currents flowing in the metal?
 
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In a permanent magnet the field comes from the individual electrons moving around the atoms. Materials are magnetic when the electron configuration is such that these individual magnetic moments add up rather than cancel out.
 
I remember it deals with the minute fields (called domains) all lining up in the same direction to compound and create a big magnetic field.
 
Thanks

Yeah, that makes sense. Thanks a lot!

The most important thing I've learned so far in university physics is to think a few steps further. Sometimes you need a little help in doing so. This forum is great
 
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