Animations of Acoustic Waves

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WAVE BASICS

 

 

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WAVE INTERACTION

 

 

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 STANDING WAVES

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HEARING SOUNDS

 

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FURTHER CONCEPTS

 

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LEARN MORE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

University of Southampton
UNIVERSITY OF SOUTHAMPTON

 

STANDING WAVES
   
Summary
 

 

 

THE NATURE OF STANDING WAVES

Standing waves may be created from two waves travelling in opposite directions. Unlike travelling waves, they do not cause a net transport of energy.

 

 

STRING MODES

Standing waves can be generated when plucking a string with fixed ends. Each mode has a wavelength and a corresponding frequency related to the length of the string.

 

 

 

MEMBRANE MODES

Membranes with fixed edges also vibrate in modes.  Their natural frequencies are not so simply related.

 

 

 

GUITAR MODES

It is the vibrations transmitted from the strings to the soundboard together with the air inside the cavity that mostly contribute to the sound perceived by the listener. Vibration modes of the soundboard can be visualized.

 

 

 

OPEN-ENDED PIPE

The natural vibrations of the air column in a pipe (like a flute) are due to standing waves or resonances. Air-reed instruments like the flute can be seen as a resonator excited by an air stream which flips in and out of the pipe at the resonant frequency of the system.

 

 

 

ROOM MODES

Standing wave phenomena can also occur in a room at specific frequencies called the resonance frequencies of the room.

 

   

STANDING WAVES

   
   

   

Room Modes