Vibrations on a Drum Skin

Vibrations on two dimensional surfaces are composed of fundamental modes which are characterized two "quantum numbers" which define their shapes. For a circular drumskin, there are two types of node: circular and transverse. (There will always be one circular node at the edge of the drum.)

Use the buttons to the left to view different fundamental modes. Each button is labelled with the two quantum numbers defining a mode. (Please be patient while the animations are downloaded.)

When you think you have worked out the relationship of the quantum numbers to the simulations, you can test yourself by clicking on the button marked "random". When you believe you have identified the vibration, click in the box below the "verify" button, then type in the quantum numbers as they might appear on the other buttons, and click on "verify. You will see a message indicating whether or not you are correct.