Pendulum Wave Machine — 15-Ball Harmonic Motion Demonstrator

Fifteen pendulums. Fifteen different lengths. One unified wave that breathes in and out of order.

The pendulum wave machine is one of the most mesmerizing demonstrations in physics. Each pendulum is tuned to complete a different integer number of swings in 60 seconds. Started together, they drift apart into apparent chaos — then synchronize back into phase with mathematical precision. The motion is purely Newtonian, governed entirely by conservation of energy and the isochronous period of a pendulum.

What you can observe:

• Simple harmonic motion and period dependence on length
• Constructive and destructive interference patterns
• Beats — the interference of two nearly equal frequencies
• Phase relationships and group velocity
• The relationship between spatial patterns and frequency ratios

Specifications: Solid hardwood frame · 15 steel ball bearings on nylon cord · Tuned to ±0.1% accuracy · Dimensions: 45cm × 30cm · Freestanding

One of the most-watched physics demonstrations on the internet. Now on your shelf.