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Why Do Discharges Arc?

  1. Aug 23, 2011 #1
    I'm interested in understanding why high energy discharges arc rather than just travel in a more direct straight path.

    Thanks for the enlightenment.
  2. jcsd
  3. Aug 23, 2011 #2
    Ionized air in an arc rises because it is hot from joule heating. I'm not entirely certain why the air glows though. In short, it's not about the shortest path, but the least resistive one, so if the conductive medium rises due to convection, then the electricity will follow.
  4. Aug 23, 2011 #3


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    Staff: Mentor

    Per here: http://en.wikipedia.org/wiki/Electric_arc

    When air is ionized, the particles don't simply stay stationary. They have very high energy and move around. I'd also guess more non-ionized air probably moves in and around the ionized air and contributes to drift and other effects.
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