Cymatics is the study of visible sound. The surface of a plate is vibrated, and the regions of displacement are made visible through a coating of particles. Various particles can be used.
Different, repeatable geometric patterns emerge. There are various ways to produce cymatic patterns. They are an enjoyable phenomenon and there are various web sites that reflect their complexity and exciting nature.
Cornstarch and water solution under the influence of sine wave vibration
Example of cymatics in action
Cymatics in Action
Cymatics in Action