Frequency is the number of occurrences of a repeating event per unit of time.
It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency.
The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency.
Relationship between Period and frequency is as under :
The frequency of a wave describes the number of complete cycles which are completed during a given period of time.
As such, frequency is a rate quantity which describes the rate of oscillations or vibrations or cycles or waves on a per second basis.
A common unit of frequency is the Hertz, abbreviated as Hz.
#color(red)("Frequency " = 1 / " Period"#
f = c / λ = wave speed c (m/s) / wavelength λ (m).