People need to play with magnets

Question from class: *What do magnets interact with?*

Basically, everyone said "metals". I am quite surprised. No one specifically indicated that magnets only interact with iron and steel (of the materials they would likely see). I understand that steel is a very common material they are likely to encounter, but what about aluminum? I think this points to the idea that very few of my students have actually played with magnets. This is a shame. Everyone loves magnets.

So, I propose you go out and give someone you love some magnets today.

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I know what you mean, but magnets interact pretty strongly with any material, and particularly conductors. Try dropping a rare earth magnet through a section of copper tubing, for example. There's a whole host of other examples, like 'levitating' aluminium blocks in MRI scanners ...

I'm sure this wasn't the idea in all - if any - of the student's minds.

Magnets interact with aluminum. That interaction is why a speedometer works (or at least a classic, non-digital speedometer). A spinning magnet induces an eddy current in an aluminum cup.

Magnets interact with Bismuth, which is highly diamagnetic. Try hanging a lump of Bismuth on a long string, and then approaching it with a magnet. Bismuth repels the field.