This java applet is a simulation of waves in a circular membrane (like a drum head), showing its various vibrational modes. To get started, double-click on one of the grid squares to select a mode (the fundamental mode is in the upper left). You can select any mode, or you can click once on multiple squares to combine modes.

Full Directions.

Full screen version.

Java Version.

More applets.

Huge thanks to Bob Hanson and his team for converting this applet to javascript.