sound: Quick Facts

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Last updated

Oct. 22, 2026

News •

Orangutans prefer food associated with sounds of laughter, study suggests • Oct. 21, 2026, 5:00 PM ET (The Guardian)

Photos and Videos

Diagram with three panels showing sound wave representations: (A) evenly spaced blue lines for air at equilibrium, (B) alternating dense and sparse blue lines for compressions and rarefactions, and (C) a yellow sine wave illustrating amplitude and wavelength.

$Diagram illustrating Huygens' principle with three panels: circular waves with wavelets forming a new front, plane waves with wavelets recombining, and sound waves diffracting around a corner due to Huygens' wavelets.$

acoustic filters typically used in air-handling systems

first three harmonic standing waves in a stretched string

first 10 notes in the overtone series of G2

first three harmonic standing waves in open and closed tubes

Helmholtz resonator

Fourier synthesis of a complex wave

Two-part diagram explaining how to estimate lightning distance by timing thunder, and how thunder is heard differently based on location. The top section shows sound waves from a lightning flash reaching an observer, with a scale indicating that thunder is heard about three seconds after the flash for each kilometer, or five seconds for each mile, up to five kilometers or three miles. The bottom section depicts two people in cars at different distances from the main lightning channel and a branc

Watch a suspended vibrating spring to learn about the propagation of sound waves

How to measure a wave: frequency and period explained

Understanding frequency and amplitude in sound

How does the McGurk effect trick your brain?

Understanding wave interference through sound experiments

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Topics

pitch specific acoustic impedance acoustic absorption monaural sound hypersound filtration echo reverberation sound localization acoustical shadow electromagnetic radiation wave Gravitational wave seismic wave longitudinal wave standing wave transverse wave bow wave radio wave elastic wave

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Key People

Hermann von Helmholtz

Hermann von Helmholtz

German scientist and philosopher

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Eric Zepler

German-born physicist

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

Physics and Natural Law

Italian physicist Guglielmo Marconi at work in the wireless room of his yacht Electra, c. 1920.

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