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Risk of lightning strike on a car.

  1. Apr 29, 2005 #1
    I understand that when lightning hits a car, the static currents stay on external surface only.

    So , can I assume that we can safely touch any parts including those metallic conductive parts on the inside of the car?
    Or would the occupants be electrocuted?

    If it were to be alternative currents and not static ones, would there be any difference?

    Thanks guys for your expert opinions.
  2. jcsd
  3. Apr 29, 2005 #2


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    Everything inside the car is at the same potential. It's a Faraday cage. So doesn't matter what you touch. I know people whose car was hit by lightning. It blew out a headlight, but they did not feel a thing.
  4. Apr 30, 2005 #3
    Is the electrical shock from lightning on a car the same as of AC electrocution?
  5. Apr 30, 2005 #4
    No, lightning is direct current.
  6. May 1, 2005 #5

    I mean, if you are inside the car and there is Ac current ontop of the car, are you as safe as when the lightning strikes?

    I mean can you can electrocuted if you happen to touch metal parts inside that car with that AC flow on its external surface?

    As for the lightning bolt, it seems we can touch anything inside the car without getting electrocuted., right?
  7. May 1, 2005 #6


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    I'm kind of curious about this too. I work with 115AC and low-voltage DC a lot. One time at a friend's house out in the forest, I was splicing a damaged extension cord back together while sitting in my car with one foot touching the ground. One of the wire strands kept stabbing me in the finger, and I was getting quite ticked off because I couldn't find the stray. Once I got it finished and shrink wrapped, I went to plug it in and found out that some twit had already done it—while I was working on it. That stabbing was actually a series of shocks. I've always wondered why it didn't hurt worse.
  8. May 1, 2005 #7
    There is still a possibility for electrocution.

    If lightning strikes the 'ground' near where you are standing, consider these scenarios -

    a) You are facing the lighting strike. It is in front of you.

    b) The lightning strikes to your left or right side.

    You are safer in scenario (a), because your legs do not bridge the voltage gradient. You will probably not be electrocuted unless you are barefoot.

    But in scenario (b), the current 'can' go into one foot and out the other. In this case you will be electrocuted.

    The same thing 'could' happen inside your car, but very unlikely because steel is a good conductor.

    If your arm was resting in the car window, and it enters/strikes your arm, you would be electrocuted. Or, if you are stepping out of the car at that precise moment it might try to exit through your foot to the earth.

    If you are in a bus, and lightning enters the bus near the driver and exits at the rear of the bus, your feet could bridge the voltage gradient if you are facing perpendicular to the direction of current travel. If you are barefoot in that bus you will probably be electrocuted.
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