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So aluminum and copper are listed as not magnetic yet powerful magnets are used to separate them from non metallic materials in recycling? Seems like a semantic argument.

https://en.wikipedia.org/wiki/Eddy_current_separator



> Seems like a semantic argument.

That kind of phrasing usually indicates someone doesn't understand or is rejecting a meaningful and useful distinction. Is that what you intended to do here?

The article seems to be pretty clear about how there are several different types of magnetism that can be exhibited by materials, and appropriately classifies various materials. Nothing about the existence or mechanism of eddy current separators is a counterexample to anything in the article.


"Magnetism is the class of physical attributes that occur through a magnetic field, which allows objects to attract or repel each other."

Aluminum is repelled by a strong magnetic field, hence the use of ECS, plastic is not. Aluminum is not Ferro-magentic it does however seem to be magnetic depending on the definition.

https://en.wikipedia.org/wiki/Magnetism

The article itself on contradictory showing aluminium as nonmagnetic then classifying as paramagnetic, which is a type of magentisim, which is it?


From the article: "Usually, when people talk about “magnetic metals,” they’re talking about ferromagnetic and ferrimagnetic metals."

Ferromagnetic and paramagnetic materials behave differently. One sticks to a magnet, the other is slowed by a magnet.


So yes they are both magnetic, thanks.


I'm not a kid, but resemble one when I get a hold of a copper tube and strong neodymium magnet. Probably my favorite toy. I'm kind of glad I have only a kid's understanding of it.


Any electrically conductive material is affected by eddy currents.




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