Ripple Tank

Apparatus:
oscillator, power supply, tank, liquid soap, water

Description:
With the tank in situ, run a bead of liquid soap on your finger and apply it to the sides of the ripple tank. Slowly add water so as not to create suds, position the oscillator such that the plungers just break the meniscus at their lowest point. The soap reduces reflections from the sides of the tank.
The speed of the plungers (point sources) is varied with the power supply, and one or two point sources may be used. The tank comes with removable barriers to show diffraction and interference.

PIRA 3B50.10, 3B50.12, 3B50.20