The Dancing Disc

Englische Version des Artikels "Die Tanzende Scheibe" 430.TSB

Kit for a large Leonhard Euler commemorative medal: complete with mirror platform on which it dances like a top for up to 1 1/2 minutes at increasing speed.

Who doesn't know this? If you give an upright coin a skilful push, it spins and spins faster and faster until it comes to a sudden halt with a splash. Thanks to its optimised properties, the dancing disc spins for a particularly long time and is noisy.

AstroMedia meets Leonhard Euler

This cardboard kit for a dancing disc is a bow to the brilliant mathematician Leonhard Euler and dedicated to his memory. It was he who first summarised the spinning process in several mathematical formulas, the Euler Equations.

A coin that spins and spins and spins

The dancing disc is considerably larger and heavier than an ordinary coin. In addition, the side edges of the disc have been optimised so that friction losses are particularly low. That is why it spins even longer and more impressively. Professionals can make the disc oscillate for over 2 minutes. The kit includes a round mirror that is slightly curved inwards and thus helps the stainless steel disc not to move too far away from the centre during its dance.

The principle

Give the dancing disc a good push with a twisting motion. Because of its weight, it tilts a little more with each rotation, becoming faster and louder in the process. To put it simply, the disc gains the energy needed for the ever faster dance from the approach of its centre of gravity to the base surface: At the beginning, it is straightened up, and the force needed for this is contained in the disc as potential energy ("position energy"). This is released when the disc tilts, and it is transformed into rotational movement energy.