I just stumbled across a new to me technology that looks like fun. I am sure several other dopers are already familiar with this technology, but for those of us just arriving at the party, here is something cool.
Simply put, this company makes magnets with multiple poles in patterns. Instead of a single N/S magnet, they build magnets with multiple N/S poles in specific patterns. The result is a magnet that acts in more complex ways-for instance repelling until they reach a certain distance then switching to attraction, attracting in certain orientations and repelling in others, etc.
Neat trick. I hope others might be interested.
Hard drive magnets have 4 poles, as described here
I’ve a small collection of rare earth magnets, and by stacking them in different patterns, I’ve created some of the same effects mentioned. Loads of fun. It wouldn’t occure to me to try to market them. Maybe that’s why I’ll never be rich.
Many years ago, my employer showed me a set of steel balls connected by what appeared to be metal sticks. It looked kind of like this, only the sticks were metal, not plastiuc as shown here:
He challenged me to figure out how they worked. The sticks weren’t simple magnets, since every end repelled every other end, and any of them could be stuck onto the steel balls at the same time, with either end (which wouldn’t happen if, say, one end of a stuck was North and the other end South). Each stick was actually composed of two magnets glued together