Editing Critical frequency (section)

== Equations ==

=== Critical frequency as a function of electron density ===
Critical frequency can be computed with the electron density given by:

<math>f_\text{c} = 9\sqrt{N_\text{max}}</math>

where ''N''<sub>max</sub> is maximum electron density per m<sup>3</sup> and ''f''<sub>c</sub> is in Hz.<ref name=":0">{{Cite web|url=http://www.rfwireless-world.com/Terminology/Critical-Frequency-and-Maximum-Usable-Frequency.html|title=CF vs MUF {{!}} Difference between CF and MUF|website=www.rfwireless-world.com|language=en|access-date=2018-09-13}}</ref>

=== Critical frequency as a function of maximum usable frequency ===
Critical frequency can be computed by:

<math>f_\text{c} = MUF*cos\theta</math>

where '''''MUF''''' is [[maximum usable frequency]] and <math>\theta</math> is the angle of incidence<ref name=":0" />