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[Osmosis Jones]

Thank you.  I'm really glad for the explanation.

Heh, my pleasure. It's not like I'm ever going to use that knowledge for anything else

[Sowelu]

o_0 Wut? That is not how magnets work, at all.

<stuff>

I wrote my honours thesis on non-conventional ways of producing ferromagnetic materials, and everytime I hear that ICP song or the bloody memes it has spawned, I start to froth at the mouth a little.

Spoiler (click to show/hide)

HONK HONK HONK HONK HONK HONK HONK HONK

HONK HONK HONK HONK HONK HONK HONK HONK

Really though, thank you for the awesome explanation!  It is very cool.  :D

[Miggy]

Hmm? I thought paramagnetic materials were the magnetic materials. Or at least, they could be made magnetic.

That's what we're taught. If the molecule/atom has unpaired electrons, it's paramagnetic and you can measure that as magnetism.

[Siquo]

Pfew, physics. Been a will since I maxwelled.
Any moving electron creates a magnetic field, so the whole spin-is-movement analogy (how right or wrong it may be) works there, too. It behaves as if it was spinning. It's just that it's so small, that in order to create a magnetic field of the size it does, according to classical physics it'd have to be spinning REALLY EFFIN HARD if it actually were spinning. So we just call it spin, and actually have no idea what that "spin" actually is.

Also, the worst gamer needs more school

[Osmosis Jones]

Hmm? I thought paramagnetic materials were the magnetic materials. Or at least, they could be made magnetic.

That's what we're taught. If the molecule/atom has unpaired electrons, it's paramagnetic and you can measure that as magnetism.

Like you said, they're basically cases where there are unpaired spins, but not enough to make a strong moment. Paramagnetic materials have a positive response to an applied field; as in, if you put a field of 10 T across a paramagnetic material, you'll get a total field of 10.00001 T out (numbers are woefully exaggerated examples). That said, because the individual moments are so weak, they don't have any exchange interactions with adjacent atoms (i.e. there are no domains, and hence no remnant field).

That said; all ferromagnetic materials are paramagnetic if you heat them up enough (over their individual Curie temperature), BUT not all paramagnets are ferromagnetic if you cool them down. I skipped over the paramagnetic case because it's not generally thought of as magnetic by most people.

While we're on it, a diamagnet is a material that has no net atomic moment. When you apply a magnetic field however, the spins of the paired electrons line up parallel and antiparallel to the field. The applied field then acts on the two orientations differently, resulting in a VERY weak net moment opposing the field. From memory, I think it's something like a 10^-12 order difference in applied field and response. Still, it can levitate frogs if you have a big enough magnet.

There're also ferri and antiferromagnets, but they suck, so I won't go into them.

Pfew, physics. Been a will since I maxwelled.
Any moving electron creates a magnetic field, so the whole spin-is-movement analogy (how right or wrong it may be) works there, too. It behaves as if it was spinning. It's just that it's so small, that in order to create a magnetic field of the size it does, according to classical physics it'd have to be spinning REALLY EFFIN HARD if it actually were spinning. So we just call it spin, and actually have no idea what that "spin" actually is.

Sort of. It works for a simple thought experiment, but the analogy breaks down really fast if you try and do a rigorous mathematical treatment, because of quantum (in the Pratchett sense). That said, my work was more experimental than theoretical, (so I didn't have to worry about it too much) and the times I tried to do it properly ended up flling a whiteboard and going nowhere.

EDIT:

Spoiler (click to show/hide)

HONK HONK HONK HONK HONK HONK HONK HONK

HONK HONK HONK HONK HONK HONK HONK HONK

Hey, Gamzee's a special case. No-one could hate him


Except for Karkat, but hey, that's Karkat.

[Siquo]

And now for the more interesting next step:

MONOPOLES, HOW DO THEY WORK?

[Osmosis Jones]

If we're talking magnetic, they really don't. By Maxwell's equations, they can't actually exist, and only drop out because of some quirks with quantum theory (which goes way over my head). Furthermore, they have never been experimentally identified, and many scientists doubt they ever will. You can however get psuedo-magnetic monopoles in things called spin-ices, but that's on a multiple atom scale, rather than the subatomic particles they're looking for elsewhere.

[Siquo]

Yeah, I read about those crystal structures, but those are not the real deal.

They're cool because they may-or-may-not exist, levitating them just above the crackpot level (the realm of perpetuum mobilae) into the "might remotely be possible".

[warhammer651]

Question: If I have a magnet, and I cut off one end using a saw, will it still function as a magnet?

[Osmosis Jones]

Better, it'll function as two They'll only be half as strong though.

[Siquo]

Also, don't let it get too hot (sawing metal makes it hot), or shake it up too much (by dropping it or trying to break it) or it will lose strength.

Edit: At home I've got a shitheap of little neodymium magnets. Those things rock.

[Argembarger]

1. Take naps in neodymium magnet pile
2. Superpowers??
3. Save world
4. Magnet Man
5. Meet Insane Clown Posse.
6. Shout, "Like This!"
7. Use Magnet Man powers on ICP
8. ? ? ?
9. Profit.

[Neonivek]

According to Comic book science magnets work as a psychokenetic force that all metals bend to.

[Virex]

Magnets: Essentially, they shunt all the electrons over into one side of the object. I don't get why this is so difficult? Or are we going deeper than this?

Erm, that's a piezo-electric material (or pyro-electric), not a magnetic one.

Hmm? I thought paramagnetic materials were the magnetic materials. Or at least, they could be made magnetic.

That's what we're taught. If the molecule/atom has unpaired electrons, it's paramagnetic and you can measure that as magnetism.

Like you said, they're basically cases where there are unpaired spins, but not enough to make a strong moment. Paramagnetic materials have a positive response to an applied field; as in, if you put a field of 10 T across a paramagnetic material, you'll get a total field of 10.00001 T out (numbers are woefully exaggerated examples). That said, because the individual moments are so weak, they don't have any exchange interactions with adjacent atoms (i.e. there are no domains, and hence no remnant field).

That said; all ferromagnetic materials are paramagnetic if you heat them up enough (over their individual Curie temperature), BUT not all paramagnets are ferromagnetic if you cool them down. I skipped over the paramagnetic case because it's not generally thought of as magnetic by most people.

While we're on it, a diamagnet is a material that has no net atomic moment. When you apply a magnetic field however, the spins of the paired electrons line up parallel and antiparallel to the field. The applied field then acts on the two orientations differently, resulting in a VERY weak net moment opposing the field. From memory, I think it's something like a 10^-12 order difference in applied field and response. Still, it can levitate frogs if you have a big enough magnet.

There're also ferri and antiferromagnets, but they suck, so I won't go into them.

Arn't ferrimagnetic materials usually very hard magnetic (or was it very soft magnetic?). I recall them having uses in specific circumstances at least, though they didn't have much to do with exerting magnetic force. Antiferromagnetic materials are used in Spin valves, which are a primary component of hard disks.

[Fossaman]

The only explanation I've ever seen for electromagnetism that made sense of the whole action-at-a-distance thing was Virtual Particles. But that's one of those things that makes me suspect physicists are making it all up as they go along. It just sounds too wacky. (Also I'm not sure if that's still current, the book I read about it in is 30 years old now.)