Investigation of mechanical waves

This experiment shows how the propagation of mechanical waves can be investigated so that a relationship between the speed of the wave and the tension can be established.  A simple apparatus composed of a central tape and a set of pendulums made of short, weighted rods placed along the tape makes the observation of the waves particularly easy, as the velocity of the waves is quite slow.   Waves are set in motion using a signal generator coupled to a pendulum at one end of the device.  Waves then propagate along the tape and reflect at the end causing interference.  Standing waves are created at specific wave frequencies, and it is the observation of these that enable the velocity of the wave to be calculated.