Coupled Pendulums

These two pendulums are connected through a common support, so the motion of one can influence the other.

Start one pendulum swinging while the other is still. Gradually, the first swing becomes smaller while the second grows larger. The energy is being transferred back and forth between them through the coupling.

After a while, the motion can return to the first pendulum and the cycle repeats.

You’ll find a small pair indoors and a big pair on a steel frame in the garden. Try both and compare how fast the swing passes between them.