# Formula Phase Velocity of a Wave Angular frequency    Angular wavenumber

## Phase velocity

Unit
Phase velocity indicates the velocity of the points of the same phase. So this could be for example the velocity of a wave crest.

The phase velocity of electromagnetic waves is the speed of light $$c$$. (Note, however, that it can be exceeded in the case of matter waves or in waveguides).

## Angular frequency

Unit
Angular velocity is the phase angle covered by the wave per second.

## Angular wavenumber

Unit
Wavenumber is related to wavelength $$\lambda$$ as follows: $$k ~=~ \frac{2\pi}{\lambda}$$.