is the quality of occurring at regular intervals or periods (in time
) and can occur in different contexts:
- A clock marks time at periodic intervals.
- A metronome ticks at periodic intervals of time.
- A publication published at periodic intervals can be called a "periodical", for example a magazine.
- In mathematics, a function whose output contains values that repeat periodically is called a periodic function.
- In chemistry, the periodic table is a table which classifies the chemical elements by means of the periodicity of their chemical properties.
- In physics, period is the number of cycles as a result of time (time/cycle). The amount of time it takes to complete one full revolution. Period is also the inverse of frequency.
- In music theory, periodicity is described as "predictability gives rise to expectations".
- Standing waves crest at periodic intervals of distance.
- In finance, the periodicity of a loan describes the interval between payments.
- The measure of periodicity in time is frequency which has the metric units of Hertz.