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How Do 'Singing Magnets' Work?
dpbsmith asks: "Singing magnets are available at all of the usual geek-toy emporia, and, for all I know, ordinary toy emporia as well. They consist of a pair of magnets made of a polished substance with the general appearance of hematite. What is surprising, pleasing, and unexpected is that when the magnets strike each other under their own power, they produce a sharp, loud buzz that rises in pitch. The sound lasts a good fraction of a second and climbs somewhere into what sounds like the 200-500 Hz range. The exact sound and its duration are somewhat unpredictable and depend on how the magnets happen to strike each other. It is a little like the sound that you get when you mash a pingpong ball against a pingpong table with a paddle. What physics are involved in the production of these sounds?"
"Google searches turn up some forum postings that indicate that it is a synthetic magnetic substance similar to hematite that's available cheaply in China as an industrial byproduct. The singing magnets are a little larger than size of olives; the shape is similar to a (U. S.) football but slightly more elongated. Their major axis is about 5 cm long, their minor about 1 cm. They are fairly powerful and will jump together when placed on a desk about three inches apart. They can distort the colors on a CRT display from a distance of over 20 cm.
Contrary to expectation, the poles of the magnets are oriented along one of the minor axes of the ellipsoid, not the major axis.
Neodymium magnets in 'ordinary' shapes produce boring 'plinks' when they snap together. Something about the shape of these magnets makes the sound much longer-lasting and entertaining. It is not simply the bounding rebound of two objects made of stiff-but-elastic material. Transfers of linear to angular momentum are clearly involved.
If course, I'd love to know whether these things were 'invented' or 'discovered', and by whom, trying to do what.
Contrary to expectation, the poles of the magnets are oriented along one of the minor axes of the ellipsoid, not the major axis.
Neodymium magnets in 'ordinary' shapes produce boring 'plinks' when they snap together. Something about the shape of these magnets makes the sound much longer-lasting and entertaining. It is not simply the bounding rebound of two objects made of stiff-but-elastic material. Transfers of linear to angular momentum are clearly involved.
If course, I'd love to know whether these things were 'invented' or 'discovered', and by whom, trying to do what.
This is clearly the work of witchcraft! BURN HIM!!!
No make that scream...
I took the magnets out of an old SCZI drive bigger than my head, and pried them apart with a screwdriver.
Well I was holding a magnet in each hand, and while I was walking they got a little too close, and my was caught in-between. Oh I sang, like a little girl in church choir.
Long story short, I didn't need stitches, but I did have one very bruised bone, not to mention my ego...
Go ahead and call me unreliable; reliable is just a synonym for predictable.
Holy. Fucking. Shit. Audiophiles are the stupidest people on earth.
- "Hear that?! The percolations are imminent! Cease your ingress!"