Saturday, April 27, 2013

(44) Lightning.

  The air around Earth is full of electrons with one of their common qualities expressed as potential and given in units called Volts. The Earth surface itself is largely devoid of electrons, has zero potential, zero Volts. The electrons in surrounding air occur in quantities increasing with the distance from the surface of Earth, and their potential is measurable.   For instance, the potential as close as 1 metre to the surface of Earth is approx. 100 Volts, and this potential is increasing at the rate of approximately 100 Volts per every 1 metre, refer
  Thus at the distance of, say, 1000 metres from the surface of Earth the potential is 100,000 Volts! The value of potential is not constant, and varies with the time of day, amount of water in the air, etc.
One of electrons‘ properties is their propensity to move from areas of higher potential to areas where the potential is lower. That property is utilised in construction of various machines, for instance light bulbs, electro-magnets, etc. Difference in potential is useful in cooking, where suitably constructed piece of material is connected between 0 and 240 Volts. Electrons in controlled amount are „travelling“ from the point of higher potential to the point with lower potential, and in their journey they heat the material connected between the 240 and 0 Volts. Electrons in the air are prevented from travelling from areas of higher potential to the areas of lower potential by air, which acts as an insulator; thus areas of different potential remain at their respective distances from Earth, give or take. And now about the lightning.
  The air contains various impurities, including water in various shapes, from microscopic particles of dirt and water through fog (clouds) to rain, snow and hail. If the air mass becomes saturated by water it ceases to be an insulator, and gradually turns into a conductor, of electricity.
  When such a water-saturated mass of air (a storm cloud, for instance) moves between areas of suitably high potential difference, the electrons utilise this „conductor“ for their travel from high potential levels to low potential levels. This „travelling“ takes place through areas of the lowest resistance, heats the „conductor“ up, which is manifested by both light and sound, and which we call lightning.
  This is a basic representation of conductive areas being formed in a developing cloud:

  From electrical point of view, a lightning is the same phenomenon as the burning filament in an ordinary household bulb (or an arc).
  Note: not sure as yet how to explain the ball lightning, except that it may not be an electrical phenomenon at all (perhaps residual plasma from the lightning channel?).

The following esoteric text appeared in the Wikipedia as one of the reactions to the above article:
This talks about potential through the air, but uses non-descript details and is far from "modeling" specific. Upon finishing reading it, understanding how lightning works, I am left with the idea that "discharge" occurs in this massive, 3-dimensional rectangle that comes down from the sky using every water molecule/impurity in the air as the conductive path. We know this is not the case, and in fact the conductor, the flash channel, is an ionized "tube" of sorts only a couple of centimeters in diameter if that. Also, the potential in the air is realitively accurate, however it fails to mention the increases due to a storm cloud passing are significant, and the origin of lightning from a clear sky is non-existant (traveling miles from a storm cloud, the "bolt from a blue", comes from a cloud, not clear sky). PS, it's an unsourced blog at that. Borealdreams (talk) 22:20, 23 March 2014 (UTC)

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