Uploaded January 2023 | Updated September 2026, 1 week ago
Thirteen uncoupled pendulums of monotonically increasing lengths, swing together by electronic oscillators to display patterns that look like traveling wave, standing wave, and beat mode.
The period of one complete cycle is 60 seconds. The longest pendulum was adjusted to complete
52 oscillations in this period. The length of each successive pendulum was adjusted to complete
one additional oscillation during this period.
Chapters
01:00 Pendulum wave patterns
01:20 Charging the Glow-in-Dark disks
01:28 Pendulums are lined up and set in motion
01:47 Sinusoidal transverse traveling wave pattern
02:07 Standing wave pattern — full wavelength
02:11 Pendulums are at alternating maximum phases, 30 seconds after they were set in motion
02:13 Standing-wave pattern — half a wavelength
02:28 Sinusoidal transverse traveling wave pattern in the direction opposite to the original one
02:41 Pendulums are ultimately lining in phase (almost…)
03:35 Idling oscillator — no swinging pendulum
03:45 Pendulum-driven by oscillator
04:00 Verifying period of pendulum with photogate
04:24 Description of circuit operation
Watch mechanical and computer-animated pendulums in action:
youtube.com/playlist?list=PLCbYhDNjOviGGaUfn9sqxT2sFq-f14T_d
And this playlist:
youtube.com/playlist?list=PLCbYhDNjOviGeNU4khuWFzLQhB2CUrYbX
Music
Title: "Moonlight" Sonata No. 14, Op. 27, No. 2 (1st movement: Adagio Sostenuto), Aug. 2, 1802
Composer: Ludwig van Beethoven
Artist: Marnie Laird for Brooklyn Classical, Recorded on Oct. 19, 2018
Title: Das klinget so herrlich – Die Zauberflöte, Act 1 Finale (1791)
Composer: Wolfgang Amadeus Mozart
Artist: Unknown
Instrument: Glockenspiel (manufactured by Kolberg Percussion GmbH, Uhingen, Germany, 2014)
Performance Context: Performed during a showcase of the glockenspiel
#PhysicsWithLego #pendulumwave #wavephysics #SimpleHarmonicMotion
Thirteen uncoupled pendulums of monotonically increasing lengths, swing together by electronic oscillators to display patterns that look like traveling wave, standing wave, and beat mode.
The period of one complete cycle is 60 seconds. The longest pendulum was adjusted to complete
52 oscillations in this period. The length of each successive pendulum was adjusted to complete
one additional oscillation during this period.
Chapters
01:00 Pendulum wave patterns
01:20 Charging the Glow-in-Dark disks
01:28 Pendulums are lined up and set in motion
01:47 Sinusoidal transverse traveling wave pattern
02:07 Standing wave pattern — full wavelength
02:11 Pendulums are at alternating maximum phases, 30 seconds after they were set in motion
02:13 Standing-wave pattern — half a wavelength
02:28 Sinusoidal transverse traveling wave pattern in the direction opposite to the original one
02:41 Pendulums are ultimately lining in phase (almost…)
03:35 Idling oscillator — no swinging pendulum
03:45 Pendulum-driven by oscillator
04:00 Verifying period of pendulum with photogate
04:24 Description of circuit operation
Watch mechanical and computer-animated pendulums in action:
youtube.com/playlist?list=PLCbYhDNjOviGGaUfn9sqxT2sFq-f14T_d
And this playlist:
youtube.com/playlist?list=PLCbYhDNjOviGeNU4khuWFzLQhB2CUrYbX
Music
Title: "Moonlight" Sonata No. 14, Op. 27, No. 2 (1st movement: Adagio Sostenuto), Aug. 2, 1802
Composer: Ludwig van Beethoven
Artist: Marnie Laird for Brooklyn Classical, Recorded on Oct. 19, 2018
Title: Das klinget so herrlich – Die Zauberflöte, Act 1 Finale (1791)
Composer: Wolfgang Amadeus Mozart
Artist: Unknown
Instrument: Glockenspiel (manufactured by Kolberg Percussion GmbH, Uhingen, Germany, 2014)
Performance Context: Performed during a showcase of the glockenspiel
#PhysicsWithLego #pendulumwave #wavephysics #SimpleHarmonicMotion
