Euler's Disc is a fascinating physics gadget, named after the famous Swiss mathematican Leonhard Euler...
Euler's Disc is a fascinating physics gadget, that was invented by Joseph Bendik in the late eighties of the last century and has been one of the most popular physics toys ever since. The 3" diameter disk is chrome-plated and spins on a 9" diameter concave mirror. This spinning disc teaches a number of important principles in physics, such as the law of conservation of energy and conservation of angular momentum. Over the years it has even inspired research papers.
Giving the disc an initial spin on a smooth surface, it starts to roll and spin, such movement is also called spolling. Spolling can last a long time and at an ever-accelerating pace. Since there is a little friction between the disk and the mirror, it can take up to two minutes, before the disc stops.