School of Physics Lecture Demonstration Manual

Wb-8 Toothbrush Wave Generator

Published: Tuesday 05 June 2007 - Updated: Wednesday 30 March 2011


To demonstrate standing waves on a string using an electric toothbrush as the vibrating source



Click on pictures to enlarge.

Tooth Brush Wave Gen Pic

Toothbrush Wave Pic 1

Toothbrush Wave Pic 2


An electric toothbrush may be used as the vibrating source for the Melde experiment. A light string attached to the vibrating head of the toothbrush passes over a pulley and weights are attached to vary the tension. The string has been coated with fluorescent paint and if used with an ultraviolet light source the modes of vibration may be easily demonstrated to a large class.

Safety notes


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