My friend and I have been pondering this question for awhile, but we don’t have an answer.
For the sake of the question, assume a preface of, “If it were possible,” because I suppose it isn’t. But say you had two magnets aligned in a linear accelerator with their north or south poles facing each other; i.e., the two ends are inclined to repel each other. Then you got them going really fast on a collision course. I guess we will have to further stipulate that they are confined in a very narrow tube or something so that they cannot turn aside.
What happens at the collision point? Will they smash into each other if there is enough force? If there wasn’t enough force, would they stop a small distance apart? Would they actually be pulverized by each others’ magnetic fields smashing into them, without ever touching themselves? What would the result look like, i.e., what kind of paths would the resulting bits of magnet take? And, would they probably cohere into a couple of lumps after the smash?
Idle curiosity, but I really want to know. Thanks!
P.S. I understand that macro matter probably won’t be smashed into subatomic particles. I’m asking about the mechanics of magnetism and matter.
I would like to put out that I am NOT a professional in the matter and might be wrong, but I would like to put out what I think would happen. If you are in possession of an EXTREME magnet, then they would very likely not touch at all. They would not “Pulverize” each other. But with weak magnets, they would likly touch and nothing amazing would happen.
Can you force two magnets to touch North-North, or South-South?
Sure.
The magnetic force is not very strong. If you got two magnets up to close to the speed of light, the kinetic energy in them is going to exceed the magnetic repulsion by countless times. And, at that speed they would vaporize (and probably take a big portion of the collider along with them (k=1/2 mv^2, so a 1-gram magnet moving at 299,000 m/s would have 44700500 joules of energy. About the same as 10 kilograms of TNT).
You can smash two magnets together, with enough force to smash them into bits.
Some magnets lose a great deal of their magnetic properties when physically shocked. But it is likely that the bits of the magnets would become smaller magnets, with north and south poles. Magnets constituent parts are magnetic “molecules”? aligned in common north south orientation.
Magnets are magnets because their atoms have intrinsic atomic properties; to get a macroscopic permanent magnet like a common bar or horseshoe magnet, you have to align the atoms such that their magnetic poles add up to a really big magnet as opposed to being all jumbled and cancelling each other out.
So, what happens when the atoms get disordered, through something like high heat or a big physical shock? You no longer have a magnet. The atoms aren’t arranged right, so that large-scale property is lost, and you have some substance which no longer exhibits any noticeable magnetic properties.
(For reference, the temperature at which a permanent magnet loses its large-scale magnetic properties is called its Curie temperature. The Curie temperature of iron is about 1043 K (1418°F, 770°C).)
So if you hit them together hard enough, they’d shatter, and the pieces may or may not be magnetized anymore. The atoms would be, but the big visible chunks wouldn’t necessarily be.
Playing with a metal around its Curie temperature is a great way to get a more visceral feel for what ferromagnetism is all about. Gadolinium, a metal that looks and feels about like iron or nickel, has a Curie temperature around room temperature. If you hold it under cold running water, it’s magnetic and you can pick it up with a magnet. If you hold it in your hands, this goes away and it feels no more magnetic than aluminum or copper. If you warm it up and then cool it down in a magnetic field, it becomes a permanent magnet and can lift other things; then warm it in your hands outside of the magnetic field and the magnetism melts (this is a great way to think of the Curie temperature, as the melting temperature of the magnetism itself).
Permanent magnets are just things that enhance the magnetic fields of their atoms in an organized way. They wouldn’t be that special in a linear accelerator.
Smashing two magnets together is almost what particle accelerators do. Two electrons, say, so two particles that repel each other (technically electric field rather than magnetic because there’s no dipole, but the math is similar). The electrons get really close, and you get so much energy in the field between them that the particles effectively disintegrate into a shower of other particles.
Replace electron with magnet, and the result is similar. At the bulk level, magnetism is weak enough you can smash the magnets together and break them into pieces. For one real life example, see if you can find the Mythbusters Bond special. They tested the ‘magnetic watch that will deflect bullets’, which is basically your scenario.
If you have a tiny magnet, say a polar molecule, you can get them close to each other, put energy into the field, and boom. Same result as electrons. That whole ‘electricity and magnetism are the same thing’ is why you can use magnets to smash electrons.
