Changes

'''Frequency''' is the [[number]] of occurrences of a repeating [[event]] per unit [[time]]. It is also referred to as [[temporal]] frequency. The period is the duration of one [[cycle]] in a repeating event, so the period is the reciprocal of the frequency.

'''Frequency''' is the [[number]] of occurrences of a repeating [[event]] per unit [[time]]. It is also referred to as [[temporal]] frequency. The period is the duration of one [[cycle]] in a repeating event, so the period is the reciprocal of the frequency.

==Definitions and units==

==Definitions and units==

For cyclical [[processes]], such as [http://en.wikipedia.org/wiki/Rotation rotation], [http://en.wikipedia.org/wiki/Oscillation oscillations], or [[waves]], frequency is defined as a [[number]] of [[cycles]], or periods, per unit time. In [[physics]] and [[engineering]] [[disciplines]], such as [[optics]], [[acoustics]], and radio, frequency is usually denoted by a [[Latin]] letter f or by a Greek letter ν (nu).

For cyclical [[processes]], such as [http://en.wikipedia.org/wiki/Rotation rotation], [http://en.wikipedia.org/wiki/Oscillation oscillations], or [[waves]], frequency is defined as a [[number]] of [[cycles]], or periods, per unit time. In [[physics]] and [[engineering]] [[disciplines]], such as [[optics]], [[acoustics]], and radio, frequency is usually denoted by a [[Latin]] letter f or by a Greek letter ν (nu).