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About how to prevent being struck by lightning

by kuengb
Tags: lightning, prevent, struck
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LURCH
#19
Oct21-06, 08:45 PM
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Yes, the car acts as a Farraday Cage (during a lightning storm the tires are almost always covered with a film of dirty water that makes a great connection to ground.

Anybody ever see that video of the Blazer getting hit?
moo
#20
Oct21-06, 09:31 PM
P: 44
Rubber tires actually have a high carbon content, which is an excellent conductor.

On a side note - a rubber automotive heater hose will carry enough current to short an electric fence. Lol, don't ask...

moo
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Loren Booda
#21
Oct21-06, 11:01 PM
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Don't forget the tires' steel belts.
Cyrus
#22
Oct21-06, 11:12 PM
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A few years ago I remember hearing on the news about a police officer who was in his car that got struck by lightning and had to go to the hospital with minor injuries.

Lightning will never strike the same place twice during a storm, so if you see it strike a tree, you should run to that spot for cover.
moo
#23
Oct22-06, 03:13 AM
P: 44
Lightning will never strike the same place twice during a storm, so if you see it strike a tree, you should run to that spot for cover.
Uh... never say never?

Once the electric potential is discharged, it should take a bit of time to build up again - but if the original conditions still exist, there's no reason it can't happen again.

Of course if it destroyed the tree, the lightning rod won't be as tall. Lol, it'd prolly be about your height...

moo
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triden
#24
Oct22-06, 02:59 PM
P: 173
Quote Quote by HallsofIvy
No, the main point about an automobile is that it is sitting on rubber tires which are insulators- lightning can't get from the car to the ground and so wont strike the car.

By the way, sitting in a SMALL hollow or in a SHALLOW cave, is not a good idea. Lightning, running along the surface of the ground can jump small distances, possibly passing through a person. Also, if you are in contact with the ground, you can be hit. Backpackers often take off their back packs and sit ON them during a thunderstorm.

There was a video on the news about 2 weeks ago about a car driving down the interstate that got struck by lightning. The video was the guy following it, lighting hit and sparks went everywhere. It was pretty impressive. Noone was hurt of course.
Alex4eva
#25
Oct22-06, 08:38 PM
P: 2
Well , i think this is a good topic for me to post my question about lightning.

I think there are devices/equipment to detect lightning strikes. But how does the device actually work? Lightning strike randomly to the ground and we have no idea where it will hit right?
moo
#26
Oct23-06, 05:08 AM
P: 44
Lightning strike randomly to the ground and we have no idea where it will hit right?
Lightning often strikes repeatedly in higher locations (hills, mountains) and tall objects such as towers and trees (although a tree may not be good for many hits). Like any short circuit, it constantly seeks the nearest discharge path.

Detecting lightning activity and pinpointing a strike's exact location is two different things though. You can detect lightning activity with an AM radio, and I've seen plans on the internet for a simple "lightning detector". More sensitive equipment can likely differentiate between "cloud-cloud", and "cloud-ground" strikes.

Determining an exact strike location may require sensors scattered about to pick up enough info for triangulation though, not real sure about this.

moo
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sdemjanenko
#27
Oct23-06, 08:59 PM
P: 33
if the car is struck by lightning then most likely the current will jump from one of the wheels to the ground via breaking down the air inbetween since it is the path of least resistance. It wouldn't enter the car.
brewnog
#28
Oct24-06, 12:07 PM
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To answer the original question, the reason to put your feet together is to minimise the step potential.

If lightning struck a short distance away (a tree or other protrusion), the potential difference between your two feet could cause enough of a current to pass through you to cause problems. This is why cows are particularly vulnerable to being killed in a thunderstorm; they don't necessarily get struck directly. The closer together your feet are, the less the step potential between your two feet.

http://oberon.ses.nsw.gov.au/resources/LIGHTNIN.HTM


Contrary to what has been said, lying down flat on the ground is NOT the thing to do, for exactly this reason.
Alex4eva
#29
Oct26-06, 12:49 AM
P: 2
Moo,
Take a look at here.

http://www.howstuffworks.com/gadget47.htm
Loren Booda
#30
Oct26-06, 10:18 AM
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According to "Fox Mulder" on "X-Files," lightning has a characteristic 8 Hz signature. "Schumann Resonance" according to Google.
moo
#31
Oct26-06, 12:13 PM
P: 44
Thanks for the link Alex4eva.

The link I had for the homemade detector mentioned earlier is dead, but here's an image I had saved. The ferrite rode is inside a PVC pipe with end caps.

moo
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tehno
#32
Oct28-06, 02:20 PM
P: 363
Quote Quote by Loren Booda
Lightning, about 100,000,000 volts of it, travels through air, a pretty good insulator, often more than a mile to the ground. How can 6" of tire compare?
It's nonsensense to say that lightning is about 100 000 000 V.
Even aproximately.
Nobody has ever measured lightning potential (I think it's impossible ).
Only you can do is to measure currents and the induced potentials in struck objects.
Loren Booda
#33
Oct28-06, 03:37 PM
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tehno,

Just Google "lightning volts" and you may have your answer.

"Sometimes I've believed as many as six impossible things before breakfast."
tehno
#34
Oct29-06, 12:21 PM
P: 363
Quote Quote by Loren Booda
tehno,

Just Google "lightning volts" and you may have your answer.

"Sometimes I've believed as many as six impossible things before breakfast."
"The Google answer" vary between 10,000,000 V and 1000,000,000 V.
3 order of magnitudes..And that's just an aproximation
SF
#35
Oct29-06, 04:29 PM
P: n/a
Well, I'd reckon since not all clouds are the same, the lightnings must also be different :)
indoforce
#36
Oct30-06, 06:56 AM
P: 3
So if standing with feet together is safer, would it be safest to stand on the toes of one foot?


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