Themes > Science > Physics > Acoustics > General Properties of Sound > Frequency

The frequency is the number of cycles of oscillation per second made by the sound source and the particles in the medium. The frequency of an audible sound is called its pitch. Frequency is expressed in "hertz."
 
Units of Frequency
1 hertz (Hz) 1 cycle per second
1 kilohertz (kHz) 1,000 cycles per second
1 megahertz (MHz) 1,000,000 cycles per second


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