PURPOSE: To show that a standing wave is the superposition of two oppositely directed traveling waves.
DESCRIPTION: A small apparatus with a hand crank sits on the overhead. Turn the crank to show the superposition of two traveling and a standing wave. As shown in the above photo at left, the wave at the top travels to the right. The wave at the bottom travels to the left. The wave in the middle is the superposition of the top and bottom waves.
EQUIPMENT: Hand crank apparatus.
Updated by Jun Qi in 3/24/2000