Amplitude
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Subject classification: this is a physics resource. |
The amplitude or peak amplitude of a wave or vibration is a measure of deviation from its central value. Amplitudes are always positive numbers (for example: 3.5, 1, 120) and are never negative (for example: -3.5, -1, -120). Amplitudes are positive because distance can only be greater than zero or equal to zero; negative distance does not exist.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Wave_characteristics.svg/250px-Wave_characteristics.svg.png)
The distance from the top of one peak to the bottom of another is called peak-to-peak amplitude. Another way to describe peak-to-peak amplitude is to say that it is the distance between the maximum positive value and the maximum negative value of a wave.
Vertical distribution of the deep water waves amplitudes is shown below:
![](http://upload.wikimedia.org/wikipedia/commons/4/4a/Deep_water_wave.gif)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png)
Wikimedia Commons has media related to Vibrations.
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Look up Amplitude in Wiktionary, the free dictionary. |