The effects of interparticle collisions on magnetohydrodynamic theory

Magnetohydrodynamics is concerned with the motion of electrically conducting fluids or ionised gases under the influence of electromagnetic fields. The theory of magnetohydrodynamics (or hydromagnetics*) applies only when the ionised gas is considered to be a continuous, fluid-like medium. When the behavior or characteristics of the individual particles composing the gas cannot be ignored, sthe theory of ionised gases must be applied instead. The purpose of this paper is to investigate the effects of collisional processes occurIng within the gas. It will be shown that the applicability and validity of magnetohydrodynamic theory depends upon the frequencies and types of collisions of the gas particles. A brief introduction to ionised gas - and magnetohydrodynamic theory has been included in order to provide a general background.