Okay, completely random idea, that probably wouldn't work, but may lead to some interesting ideas, heh.

I was looking at those really strong neodymium magnets earlier, and had a weird thought. Would it be possible to mount two or more of them facing each other at a certain distance and secure them.
Then if a metal object like car keys or something was placed in the middle of them that it may sorta float in between, since neither magnet can overpower the other. Except you would need a slightly stronger magnet on top to counter gravity's help to the bottom one. Which could maybe be done by adding smaller magnets onto it in even patterns.

That's just a rough general idea, but I think anything along these lines might be cool, but probably near impossible or only possible in a vacuum or something. But thoughts?

It would be impossible to balance the keyring between two permanent magents in such a way, but thats not to say the system is completely impossible.

Check this out: http://bea.st/sight/lightbulb/

If you really want to pursue it, you may even want to contact the guy who made it.

Keys are usually made of brass & brass is nonmagnetic, so no, that wouldn't be possible. ;)

But I'm sure it would be possible to suspend something b/w 2 magnets as long as it's in precisely the right position. I don't think you'd even need the third magnet to counter the force of gravity.

The only way to really be able to do it is electromagnets and circuitry. You can do a trick like this:

http://en.wikipedia.org/wiki/Image:Diamagnetic_graphite_levitation.jpg

with nonelectric methods, but emags and stuff is the way to go for legit levitation.

It is nearly impossible to do with permanent magnets. Electromagnets may work with feedback mechanisms, but it is still difficult. The simplest way would be to use superconductors. Another benefit is that you will only need one magnet.

The best material is yttrium barium copper oxide. It only needs liquid nitrogen to keep it cool. Liquid nitrogen is cheap (around $2 per litre).

Of course all of this will fail if you use brass keys :rolleyes:

Why can't you just get a steel key (I know it will be more expensive to machine, but it's for the sake of novelty, so cost isn't such a big deal anyway) and then magnetize it, and suspended it above on big magnet? Theres been pens that float in the magnetic field above their rests out for years.

Why can't you just get a steel key (I know it will be more expensive to machine, but it's for the sake of novelty, so cost isn't such a big deal anyway) and then magnetize it, and suspended it above on big magnet? Theres been pens that float in the magnetic field above their rests out for years.

Because it is unstable and will fall off.

Superconductors are the way.

Because it is unstable and will fall off.

Superconductors are the way.

..No, it won't. It will stay in the one place and you can even spin it in place. These things already exist without any problems whatsoever, I remember seeing the best example of one as a kid at a friends house - his pen would float horizontally above a magent and in between two sheets of plexiglass, at a height of around 80mm (floating height).

These things aren't hard to make, you just need to do the calculations correctly.

..No, it won't. It will stay in the one place and you can even spin it in place. These things already exist without any problems whatsoever, I remember seeing the best example of one as a kid at a friends house - his pen would float horizontally above a magent and in between two sheets of plexiglass, at a height of around 80mm (floating height).

These things aren't hard to make, you just need to do the calculations correctly.

You need the magnet to be a bowl shape. It will work of course since the thing cannot fall out, but if you want something small and flat superconductors are the way.

It is nearly impossible to do with permanent magnets. Electromagnets may work with feedback mechanisms, but it is still difficult. The simplest way would be to use superconductors. Another benefit is that you will only need one magnet.

The best material is yttrium barium copper oxide. It only needs liquid nitrogen to keep it cool. Liquid nitrogen is cheap (around $2 per litre).

Of course all of this will fail if you use brass keys :rolleyes:

where could one get liquid nitrogen for ~$2/L?

Buy a 500L container? I think liquid nitrogen is a bit more expensive than $2/L.

actually:

http://www.colorado.edu/propertydistributionservices/ln2.htm

actually:

http://www.colorado.edu/propertydistributionservices/ln2.htm

There you go. 50c per litre.

It can't be that hard to make or find. 70% of the air is nitrogen. To make it they compress air. When air is compressed it heats up so they cool it back down to room temperature. Then they distill the nitrogen. That is why it is cheap.

Feh, I haven't been find any LN2 around here (Detroit) for under $10/L. Unless you're buying massive quantities of it.

Probably because where you're looking, you're paying for the container too.

A cardinal rule for home chemists is this: If you're looking for a chemical, don't buy it from a scientific supplier if you can help it. Look for a retail outlet that sells it for something else. A good example is copper sulfate and sulfur. Both are fairly expensive when bought from a chemical supply company, but are CHEAP as HELL at Ace hardware. Copper Sulfate is sold as root killer, and sulfur is also sold in the garden area.

I'd be willing to bet that the same is true for LN2. Do a bit of research and try to find out what people usually use it for. Then look there!