Editing Coupling (physics) (section)

==Plasma==
{{main|Frequency classification of plasmas}}

The coupling constant of a [[Plasma (physics)|plasma]] is given by the ratio of its average [[Coulomb interaction|Coulomb-interaction]] energy to its average [[kinetic energy]]—or how strongly the electric force of each atom holds the plasma together.<ref name=":1">{{Cite book|title=Plasma Physics|last=Ichimaru|first=Setsuo|publisher=Benjamin/Cumming Publishing Company|year=1986|isbn=978-0-8053-8754-4|location=Menlo Park, California}}</ref> Plasmas can therefore be categorized into weakly- and strongly-coupled plasmas depending upon the value of this ratio. Many of the typical classical plasmas, such as the plasma in the [[solar corona]], are weakly coupled, while the plasma in a [[white dwarf]] star is an example of a strongly coupled plasma.<ref name=":1" />