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Old 06-03-2015, 07:55 PM   #1
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Default Lightning vs Car vs You

What happens when lightning hits a car...with you in it?

http://abcnews.go.com/US/lightning-s...ry?id=31497055

You will likely survive.
The car will likely not survive. with all the electronics blown out, half the windows, a couple of tires and the air bags.

In fact, it may even burst into flames.

A sturdy building is your best bet.
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Old 06-03-2015, 08:16 PM   #2
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Faraday shield.
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Old 06-03-2015, 08:59 PM   #3
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A metal car body is indeed a pretty good Faraday shield -- most of the time -- but not necessarily during a lightning strike.

First, let's wonder what resistance might exist between the floor pan and the roof. I'd think it would not be less than about 0.01 ohm. Could be much more if body panels are poorly bonded.

What's the current in a lightning bolt? References that I've seen say typically about 30,000 amperes, but often as much as 120,000 amperes.

Now suppose that lightning current is flowing upward from ground through your car, because the lightning bolt chose your car as a target. Say, 120,000 amperes through your car body's 0.01 amperes. During the strike, there will be 1200 volts between the floor pan and the roof. Your feet are on the floor, and your head is near the roof.

Will that Faraday shield protect you? Eh? Oh, OK. I don't think so either.
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Old 06-04-2015, 08:05 PM   #4
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Originally Posted by NN5I View Post
Will that Faraday shield protect you? Eh? Oh, OK. I don't think so either.
Proof's in the puddin'

The young lady in the video is still out walking around, sore ribs from being blasted by the airbags. And many others, to boot.

Seems the most likely way to die in this scenario is to be rendered unconscious and then the car catches fire from the strike.

Now no one is saying this is an altogether pleasant experience... and the video states the best place to be is in a substantial building.
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Old 06-05-2015, 09:50 AM   #5
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The current flows around a Faraday shield so those inside should feel no effects well I know I would probably wet my self if lighting struck my truck but the occupants should be fine. There was a utube posting a while back that was caught on a video camera of a full size pickup in Canada getting struck pretty impressive.
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Old 06-05-2015, 01:16 PM   #6
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The current flows around a Faraday shield
Indeed it does, but only when resistive and inductive effects are negligible. With lightning, because of the fast risetimes, inductive effects are important; and because of the very large currents available, the effect of even very small resistances can be cause major surprises. For lightnng, a car body is a very imperfect Faraday shield.

Taking a generality you've read somewhere, like "current flows around a Faraday shield", and applying it to very anomalous events like lightning strikes, without bothering to understand what's going on, can lead to serious errors.
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Old 06-06-2015, 09:08 AM   #7
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Don't know but aircraft get struck all the time and every one inside walks away (after they land of course) Has there been a case of lighting deaths from cars being struck I could not fine any hard evidence. The greatest casualties seems to be tires, electronics and radio antennas.
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Old 06-06-2015, 09:13 AM   #8
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Just don't have the radio mic laying in your lap when lightning comes down the antenna.

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Old 06-06-2015, 09:34 AM   #9
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Quote:
Originally Posted by Radio View Post
Proof's in the puddin'

The young lady in the video is still out walking around, sore ribs from being blasted by the airbags. And many others, to boot.
They push air bags as a safety device but every accident where air bags deploy is an injury accident..What injury..Air bag deployment injury of course.

I've seen crashes that if anything were worse.. Where the only injury was some minor brusing from the seat belt.. SEAT BELTS SAVE LIVES.. air bags are dangerous.

And yes..(to another poster) Current flows AROUND you but at that level the EMP is enough to mess up not only the car's electronics but your brain and or nerves as well.

Best plase to be when lightening strikes is...... ELSEWHERE!!!!
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Old 06-06-2015, 11:23 AM   #10
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Quote:
Originally Posted by wa8yxm View Post
They push air bags as a safety device but every accident where air bags deploy is an injury accident..What injury..Air bag deployment injury of course.
One must ask, of course, what the injuries would have been without the air bags. Typically much worse, I think. Much worse. Much.

A young person very dear to me totaled her car (no lightning involved) in Oklahoma City about three weeks ago, just three days before her high-school graduation. She had some sore places from being hit by air bags, but walked easily during the ceremony. Without air bags she would probably have sustained serious internal and external injuries and brain damage. Thank you, air bags!

She had been working hard and saving up for a better car anyway, and was well on the way to having enough. Last week, with a little help from friends (including Your Obedient Servant NN5I) she purchased a pretty little blue 2003 Mustang, and henceforth will be a better driver. Many young people total their first car and learn from it. What they learn is that it can happen to them. This is worth learning.

As for lightning, how the heck can you avoid it? The very expression a bolt from the blue means a totally unpredictable event. The metal car body, acting as a sort of makeshift (and very imperfect) Faraday shield, usually helps a lot, but I wouldn't volunteer to be a test subject. Would you, N3LYT?
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