> > Good basic introduction at http://www.physics.ucla.edu/marty/diamag/ > > Actually, according to that page, it *could* work, as long as you wanted to > levitate a frog or a chunk of carbon (graphite, etc.). Yes. But it always involves diamagnetic material of some sort. In the case of thefrog the frog is its own source. One explanation is that the strong magnetic field causes precesssion of the atoms which generates a counter field. > Seriously, though, why couldn't static levitation be accomplished using > graphite or some other strong diamagnetic material, as suggested in the > article? Couldn't ya just slap a plate of graphite over the substrate > magnets, and make the levitating widget out of graphite with a magnet at the > core? Or am I missing something, once again? It could. Yes. No. As I noted, you can't do it with static fields alone. There are numerous successful static diamagnetic levitation sites on the web. The levitating widget itself needs not use diamagnetic material > BTW, how do those levitating-pen things work? Do they have a graphite > diamagnetic on top? Or do they use an electromagnet with hall-effect sensor > feedback as demonstrated in some of the other references? Most commercial ones use electronics with feedback (usually a Hall sensor as you say). Pens that stand on their tips just use a magnet. RM -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.