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Electrical question! (well, lightning, really)

  1. May 5, 2005 #1
    Can lightning shoot up? Say someone had a device that could fire out lightning, would it shoot upwards or would it come down?
    Oh! And if the person had mechanical devices on them, like metal or something, would the lightning be attracted to it?
  2. jcsd
  3. May 5, 2005 #2
    Lightning goes from the ground to the sky. Lightning is the relay of excess charge between two conductive mediums, such as in any simple capacitor. The only difference is light travels through air, which has a dielectric constant greater than one. It would be attracted to any conductive object, just as any spark or electron "jumping the gap".
  4. May 5, 2005 #3
    So....If a person was using a device or something to shoot lightning up, it would go up, but if they had something on them like metal or a device made of metal, it would go right to that instead? Sorry, I just don't understand all of what you're saying exactly. :|
  5. May 5, 2005 #4
    This is not so simple

    The lightning "travels" via a plasmatic "track", which is created by the lightning itself.
    This is like with machine that lays the railroad tracks and advances by riding on the last layed railroad tracks and so on...

    Once the plasmatic track was defined (the lightning reached the final destignation, the track path can't change and the lightning continue with the same path untill the energy discharged...
  6. May 5, 2005 #5


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    Think of path of least resistance - since air is such a poor conductor anything that assists in letting it travel less distance across this poor conductor is the likely spot of origination. That's why things like power line poles, trees, buildings, et cetera are the likely place for it to strike and where lightning rods are located to help divert it around the structure. Not only are they made of metal, they are pointed upward and grounded electrically to assist in their probability of being the place struck.

    On the TV show "Mythbusters" they did a test to see if having a metal tongue piercing increased the chance of being struck by lightning and found no real statistical rationale for it. Our bodies are made up of a lot of water and traces of salt and other minerals are in the blood - we're not very perfect insulators and can conduct pretty well at the voltage levels of lightning.

    If you are standing in the middle of an open field in a thunderstorm this is very dangerous. Your head is now 5-6ft closer to the clouds making you the path of least resistance. And like the first 2 guys who tried to repeat Franklin's kite experiment and actually ended up with lightning found out, its not a good thing. A set of metal keys in your pocket is not a big concern, getting yourself low to the ground (to avoid becoming a lightning rod) and moving away from a lone tree that is likely to be struck and so on should be the primary concern.
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