School of Physics Lecture Demonstration Manual

Wb-1 The Melde' Experiment

Published: Tuesday 14 March 2006 - Updated: Wednesday 30 March 2011


To demonstrate standing waves on a string.



Click on pictures to enlarge.

Melde Diagram

Melde 1

Melde 2

Melde 3

Melde 4


Melde Demonstration


A light string approximately 2 metres in length is connected to a motor driven eccentric cam. The string passes over a pulley and is attached to a 100 gm. weight. A black cloth may be placed behind the string to aid visibility. As the speed of the motor is increased standing waves are observed. It is possible to obtain 6 or 7 modes and with the aid of a stroboscope the string motion can be frozen for analysis.

Safety notes

Electrical safety 


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