August 2008
Intermediate to advanced
192 pages
8h 8m
English
Mathematically rich thrills from a cheap toy.
I recently returned home from Japan with some leftover coins and decided to make them into “wobblers.” Two orthogonally interlocked disks will roll together with an amusing left-right wiggle. If the spacing between the disks is just right, the wobbler’s center of gravity remains at a fixed height so it will wobble down the slightest incline. It is surprisingly addictive to roll these and race them, and you can’t beat them as a cheap gift!