How could I develope a magnetically charged coil so that a magnet might levitate through it?

Question

I am in the process of doing a project for a science fair exhabition and I'm interested in finding out as part of my project how I might be able the make a simple bar-magnet levitate through a series of magnetically charged coils (electromagnetic of course). Basically I'm trying to find out info about the circutes I might need and also the find out about the meterials I might need. I would be grateful if you could give me any info at all, even if you have info about URL's I might be able to go to on this subject. Thank for your help.

Answer 1

You're going to have an extremely difficult time "levitating" a simple bar magnet without the use of diamagnetic superconductors and lots of liquid nitrogen (which i take it you don't have access to). In order to levetate a magnet using current-generated magnetic fields, your setup must be accurate to within millimeters, and even at that any small bump or blow of the wind would knock it out of stability. You're better off making some sort of railgun.

Answer 2

You will not be able to make it move through the coils (loops) in a horizontal manner because the effect of gravity will pull the magnet down because the field would be of equal strength through the middle. The good news is that if you used a loop structure and set it vertically you could make several loops and set the magnet inside and then using gravity and switching polarity of the loops cause the magnet to travel at a controlled rate down the "tube" essentially centered and levitated.



If you set up three rows of coils such that the sides are at an angle to the bottom and form a trough the magnet would be able to float in it. Then if you used another coil behind and one in front of the magnet that were reversed in polarity it would cause the magnet to move. The trick will be in getting enough stability in the magnet so that it does not dip at either end.

As for the construction of the coils you can use copper wire wound on a spool and connected to a power supply. The direction of current flow will determine the "magnetic polarity" of the coil and you can find this info in about any good physics book or determine it by trial and error.