Pronunciation: /ˈæm.plɪˌtud/ Explain

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What is the relationship between the amplitude and the high and low points of the oscillating function?
Manipulative 1 - Amplitude of an Oscillating Function Created with GeoGebra.

Amplitude is half the distance from the minimum to the maximum values of the range of a bounded periodic function.[1] In the simple periodic equation f(x)=a sin(bx)+c, the amplitude is |a|.

For sound waves, the amplitude is the magnitude of the air pressure. This is related to the loudness of the sound. The greater the amplitude of the sound wave, the louder we perceive the sound. For light waves, the amplitude is related to the brightness of the light.


  1. McAdams, David E.. All Math Words Dictionary, amplitude. 2nd Classroom edition 20150108-4799968. pg 15. Life is a Story Problem LLC. January 8, 2015. Buy the book
  2. Bettinger, Alvin K. and Englund, John A.. Algebra and Trigonometry. Sec. 8.4 pg 149. International Textbook Company. January 1963. Last Accessed 6/12/2018. Buy the book

More Information

  • McAdams, David E.. Periodic function. All Math Words Encyclopedia. Life is a Story Problem LLC. 6/19/2018.

Cite this article as:

McAdams, David E. Amplitude. 4/11/2019. All Math Words Encyclopedia. Life is a Story Problem LLC.

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Revision History

4/11/2019: Changed equations and expressions to new format. (McAdams, David E.)
12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)
6/13/2018: Removed broken links, changed Geogebra links to work with Geogebra 5, updated license, implemented new markup. (McAdams, David E.)
12/24/2009: Added "References" and more information. (McAdams, David E.)
11/20/2008: Initial version. (McAdams, David E.)

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