Experiment of The Month
Pendulum Traveling Wave
Rachel Macey is
The unlike the previous experiment of the month, these pendulums are all the same length. In this demonstration, the black support remains fixed. The pendulums are coupled together with paperclips, visible near the top of each pair of strings.
In order to see a wave traveling, it helps to have the bobs settle down quickly after the wave passes. The highly damped tennis ball bobs serve well for this purpose.
Below are shown a sequence of images, with Ms. Macey starting the right-most
Students liked the simplicity and the surprising motion.
Ms. Macey also showed some standing wave patterns on a Chladni plate, as in the pictures below