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OneSevenNine wrote:I fully expected an Insane Clown Posse joke when I clicked on this thread, and it saddens me that none have been made.

Techno wrote:Fucking magnets, how do they work?

Techno wrote: Fucking magnets, how do they work?

Wellllllllll...

The short of it is that a moving charge creates a field, relative to its motion, that distorts the motion of other charges. This is not quite so related to that most noted effect of a magnetic field, picking up iron filings.

Particles of the subatomic variety have a magnetic field of their own, which is referred to as spin. This is not actual spin in the sense of a spinning object, but the field generated is identical and so the particles may be assigned an angular momentum, which is always an integer or half-integer multiple of h. Adjunct to this, electrons also have an orbital angular momentum as they orbit the nucleus of an atom, and this creates a magnetic field as well, albeit a smaller one (but still relevant) than that of the spinning electron. In some atoms, such as helium, all electrons are paired, so the overall spin of the electrons is zero; in others, such as nitrogen, the electrons are not paired, and the overall spin is nonzero.

Anyway, in materials with an unpaired electron, the presence of a magnetic field causes the energy level of the case where the electron's spin is aligned with the field to decrease, and causes the energy level of the case where the electron's spin is antialigned with the field to increase; this is known as the Zeeman effect, is caused by the familiar perturbation H' = u * B. The unpaired electron will preferentially align with the magnetic field, causing the ground state energy of the atom to be lower in the presence of the field, which in turn causes it to be attracted by a field gradient.

Now, in most materials, the spin of the electron will actually not be significantly influenced by a field of the magnitude of that of a permanent magnet; the effect I've just described is known as paramagnetism, and is too weak to notice usually. However, in certain materials, such as iron, when the spin of one electron changes, it affects that of others, causing the spins of all unpaired electrons to align with the field in the presence of such, and therefore the energy is remarkably reduced in the presence of a magnetic field. This causes it to be strongly attracted to even weak fields, and is known as ferromagnetism.

So what is a permanent magnet, exactly? It is a substance in which the spins are all already aligned, producing an overall field. This alignment competes with entropy and is so reduced at high temperatures, which is why magnets can be destroyed in an oven.

romaniac wrote:About 50 - 100

New Zealand towns each have their own magnet, all in the same style, just with a different picture. My mum buys one for everywhere we have been usually.
On our fridge is a kind of graph representing each of the various locations in the country we have been, made in the shape of the country. Like, each of the magnets from southland are around the bottom of the island on the graph. It looks pretty cool.

Universezero wrote:My mum doesn't let me put magnets on the fridge. ;_;

Techno wrote:

OneSevenNine wrote:I fully expected an Insane Clown Posse joke when I clicked on this thread, and it saddens me that none have been made.

I've made this joke several times on the IRC over the past few days.

But since you noticed:

Fucking magnets, how do they work?

fine, you fucking haters

Smörgåsbord wrote:

Techno wrote:

OneSevenNine wrote:I fully expected an Insane Clown Posse joke when I clicked on this thread, and it saddens me that none have been made.

I've made this joke several times on the IRC over the past few days.

But since you noticed:

Fucking magnets, how do they work?

fine, you fucking haters

Go wash your mouth out with some Summer's Eve, asshole.

Techno wrote:Alright man, sorry. Won't happen again.