Wavenumber

Spatial frequency of a wave

In the physical sciences, the wavenumber (or wave number), also known as repetency, is the spatial frequency of a wave. Ordinary wavenumber is defined as the number of wave cycles divided by length; it is a physical quantity with dimension of reciprocal length, expressed in SI units of cycles per metre or reciprocal metre (m−1). Angular wavenumber, typically denoted by the letter k {\displaystyle k} , defined as the wave phase divided by length, is a quantity with dimension of angle per length (or simply reciprocal length) and SI units of radians per metre (or m−1).

From Wikipedia, under CC BY-SA. More on occurri.