The Kid Should See This

Harvard’s classic pendulum waves demonstration

Watch more with these video collections:

A Harvard Natural Sciences Lecture Demonstration of 15 uncoupled simple pendulums of monotonically increasing lengths swing for a minute and a half, a physics video classic.

The period of one complete cycle of the dance is 60 seconds. The length of the longest pendulum has been adjusted so that it executes 51 oscillations in this 60 second period. The length of each successive shorter pendulum is carefully adjusted so that it executes one additional oscillation in this period. Thus, the 15th pendulum (shortest) undergoes 65 oscillations. When all 15 pendulums are started together, they quickly fall out of syncβ€”their relative phases continuously change because of their different periods of oscillation. However, after 60 seconds they will all have executed an integral number of oscillations and be back in sync again at that instant, ready to repeat the dance.

Watch more pendulum videos on this site.Β 

Thanks, @imuptoolate.

🌈 Watch these videos next...

Wave Pendulum – Citadel Physics

Rion Nakaya

Understanding tether dynamics through kite flying

Rion Nakaya

Two turbines and a rope: Waves by Daniel Palacios

Rion Nakaya

This “snail shell spider” uses its web to hoist objects up high

Rion Nakaya

Thermal expansion sphere and ring demonstrations

Rion Nakaya

The synchronization of 100 metronomes

Rion Nakaya

The ORBIS FLY kinetic light system at the Leningrad Center

Rion Nakaya

The most amazing thing about domino chain reactions

Rion Nakaya

The Iron Genie Harmonograph

Rion Nakaya

Get smart curated videos delivered to your inbox.