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Lightning strike in mindair

  1. May 27, 2012 #1
    I recently watched the movie Chronicle, and in it, one character is killed when he is flying in the sky and lightning strikes him (the lightning doesn't hit the ground afterwards, if that matters). Would this actually kill someone if they weren't touching the ground when they were struck? And does the answer apply for larger bodies, such as planes?
     
  2. jcsd
  3. May 27, 2012 #2

    K^2

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    Planes get hit by lightning all the time. It usually just passes through the airplane body without harm, because fuselage is the most conductive part. Obviously, if a person who isn't sitting inside an aluminum capsule gets struck, the electricity will flow through the body, and be lethal more likely than not. However, that current still needs to flow somewhere. So a lightning can't strike a person in the air without passing through and going towards the ground or another cloud. A person cannot be an end-point for the lightning, because a person simply cannot hold that much charge.
     
  4. May 27, 2012 #3
    So if the person wasn't the endpoint and the bolt continued to its endpoint at another cloud then the person would be fine?
     
  5. May 27, 2012 #4

    Vanadium 50

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    Is the person in a metal shell or not? K^2 describes what happens in both cases.
     
  6. May 28, 2012 #5

    K^2

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    Lightning has to continue on. Situation where person is at an end point is impossible. If a lightning does hit, that is, it goes through a person, survival odds are no better than on the ground. In fact, they are probably worse. Airplane fuselage is what protects people and equipment on a flight, by providing a better path for electricity. If the choices are human body or air, however, lighting will go through the body.
     
  7. May 28, 2012 #6

    Bobbywhy

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    Jared409, Read about lightning. Get your vocabulary (terminology) straight, and don't beleive everything people casually write here without checking up for yourself. Wikipedia is not always correct, but has a pretty good record. It also gives references at the bottom for you to go into more detail.

    "Lightning strikes injure humans in several different ways:
    • Direct strike, which is usually fatal.
    • Contact injury, when the person was touching an object that was struck
    • Side splash, when current jumped from a nearby object to the victim
    • Ground strike, current passing from a strike through the ground into a nearby victim. A strike can cause a difference of potential in the ground (due to resistance to current in the Earth), amounting to several thousand volts per foot.
    • Blast injuries, including hearing damage or blunt trauma by being thrown to the ground."
    http://en.wikipedia.org/wiki/Lightning_strike
     
  8. May 28, 2012 #7

    K^2

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    And how many of these are a possibility for a person falling through the air? The difference between relying on own knowledge and Wikipedia is that former requires at least some level of understanding.
     
  9. May 28, 2012 #8

    Bobbywhy

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    Excuse me, please. I did not read and understand the OP beforehand. Thank you for your clarification. The term "person being an end point" was totally new to me. Sorry for being so hasty.
    Bobbywhy
     
  10. May 28, 2012 #9
    In every case, harm occurs only when the current enters the body on one path. And leaves via some other limb.
     
  11. May 28, 2012 #10
    Thanks, I was asking this question with the whole "birds on a wire" concept in mind, thinking that if the current was just passing through the person/object, then the body in question wouldn't be harmed. Thanks for clearing this up
     
  12. May 28, 2012 #11
    Now let's expand on that concept. Lightning struck a tree maybe 10 meters from a cow. The cow dies. Did EMF kill the cow? No. The cow was struck directly. Electricity passed through that cow.

    Lightning is a connection from the cloud to charges maybe 5 kilometers distant. An electrically shortest path might be 3 kilometers down to earth. And four kilometers through earth.

    Also in that path is a cow. An electrically shortest path is up the cow's hind legs and down its fore legs. A direct strike to that cow.

    Had the cow been surrounded by a buried wire loop, then electricity would not be incoming and outgoing. This is called a single point ground. Or equipotential. Same science is why humans are should stand with feet together. No incoming and outgoing path from and to earth.

    But again, harm from electricity can only exist when both an incoming and outgoing path exists.
     
  13. May 28, 2012 #12
    Interesting question, but can you put "Spoiler Alert" in your title.

    Sorry if that's too picky, but I hate when I'm not given the option to not be spoiled on a movie/book/whatever.
     
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