Well, I guess it's possible to make a magnet that would push objects that are conductive but not ferromagnetic towards itself. The first example that I could think of was two concentric coils that have currents flowing in opposite directions. At some point along the axis of the two coils, the fields of the two coils cancel each other out. If you put a small conductive object (like a copper disk) just outward of the "dead spot," it would tend to be pulled in, towards the dead spot. The same idea also seems to work if the inner coil is made into a shorted turn. I've attached some examples. Note, however, that the region in which the conductive disc is attracted rather than repelled is limited--if you go farther out on the axis, the force direction switches sign. Dave. -- David Meeker http://femm.berlios.de/dmeeker
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