Chladni figures-making sound visible

 

The Chladni figures are named after the German scientist Ernst Florens Friedrich Chladni (1756-1827).

Chladni excited the normal modes of thin metal plates covered with sand by stroking them with a violin bow. The Sand is pushed away from the vibrating parts of the plate and collects at the node lines. This leads to the formation of different patterns, the so called Chladni figures, which depend on frequency and plate geometry.

In our experiment the plates are excited with a vibration generator connected to a function generator. This allows a fine adjustment of the frequencies.