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Giant slalom of particles in a plasma?

  1. Feb 21, 2016 #1
    The charged particles of a plasma are either strongly repelled or attracted to one another. Am I correct in saying that they do a "giant slalom" around one another? And does this mean that the transfer of momentum in a collision is much smaller than in a neutral gas where the atoms/molecules collide like billiard balls? Where can I read up on this?

  2. jcsd
  3. Feb 23, 2016 #2


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    Not sure what you mean by doing a giant slolam around one another. But you are correct in that even small charge imbalances create large electric fields. If you go on to learn some plasma physics, you will learn the so-called 'plasma approximation' (not valid for high frequency/small scale phenomena) that exploits this fact to simplify the analysis by initially assuming the electron and ion densities are equal.

    I am fairly ignorant of collisions in plasmas. Back when I was in that field I was mostly studying phenomena in the Earth's magnetosphere, where a typical mean free path is the order of an astronomical unit so collisions could be safely neglected. Very good plasmas tend to have few large-angle collisions but many small angle collisions. One place to start reading up on collisions is in the lecture notes at:
    some notes on collsions are also in the lecture notes of

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