Posted on 05/28/2009 11:30:09 AM PDT by Squidpup
I’ve been outside in numerous sudden lightning storms in the desert. And when one strikes close, it is quite different than your normal thunder. Rather than a long deep boom, it is a quick sharp loud crack. One struck us so close one time that the flash burned red in my cornea and the crack was deafening. You can smell the ozone, and the air feels tingly. I have also been out at times where though there wasn’t active lightning happening, you could actually hear the earth crackling like a power line because the static charge was so ridiculously high. One time while out in a snow storm, even with everybodies hair soaking wet, nevertheless everyones hair was sticking straight out like they had their hands on a vandegraff generator. Cool stuff.
Perhaps Connor or Duncan missed a block...
Le Zot!
Nice zot picture ping
Actually, being inside the tower is probably the safest place there is during a storm. Google “Farraday cage”.
I’m a bit pop-culture-challenged. ‘Splain, please?
Sacré mérde!
Isn’t that how Benjamin Franklin met his demise?
Highlander...whenever one of the immortals is slain by another, there’s lots of lightning and broken glass...etc...
According to Martin Uman's classic text The Lightning Discharge, upward-initiated discharges are "relatively rare," accounting for less than 1% of all lightning, "and generally occur from mountain tops and tall man-made structures."ka-boom!
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NOPE!
Got it - thanks!
Le zot du frog.
Ooooooooo now that is the uber ultimate french zot shot!
Not really, he flew a kite during a thunderstorm and the wet string gave a few sparks from which he concluded that lightning is actually static electricity. He most emphatically did not pull down a lightning strike to his "Leyden Jar" (an early form of capacitor, used to store static electricity).
Under clear skies there is a voltage gradient from "ground" level of several hundred volts per meter of altitude. During a thunderstorm that gradient can rise to tens of thousands of volts per meter. The air currents inside a thunderhead create rising and falling streams of ice particles that act much like a conveyor belt moving electrons to the bottom of the cloud and leaving behind a net positive charge at the top.
Looking at the bottom of the cloud, which can be several acres in extent, the negative electrons are evenly spread across the bottom because all similarly charged particles repel each other. As the cloud moves along there is a mirror image of positively charged particles keeping pace with the cloud. This happens because the unlike charges have an attractive force.
As the cloud and it's mirror image on the ground move along they are separated by a dielectric (the air) which is a nonconductor. When the mirror charge encounters a conductor like a metal building or antenna, it flows up toward the cloud in the metal and if it's near the breakdown potential of the separating dielectric, continues upward as a weak ionized plasma. The cloud also starts a similar weak plasma column of opposite polarity downward.
If the to leaders meet the entire charge of electrons on the bottom of the cloud rushes toward the point of discharge and a current of several million amperes flows through a superheated plasma column of several meters diameter. Simultaneously on the ground the positive charged particles race toward the point of discharge and the opposing charges annihilate themselves.
The current flowing in the lightning stroke is the same as the current through the ground toward the discharge point. That current generates an enormous magnetic field which in turn induces a secondary voltage into any metal object that is not in contact with the ground. Consider it to be an air cored, single turn transformer, with several million amps flowing through the primary.
Telephone wires, electric fences, door knobs, stove pipes, &c. &c. can and do develop significant voltages. Many people who claim to have been hit by lightning have really suffered a shock from the secondary effects of a nearby strike. It is rather unlikely that a mortal could survive standing in a two meter diameter, 10,000° plasma, with a couple million amperes passing through a body comprised of mostly salt water. The most likely outcome would be a loud steam explosion and maybe twenty pounds of glowing charcoal.
Regards,
GtG
PS Franklin died on April 17, 1790, at age 84, long past his dalliance with lightning.
ping
;o)
In the series Highlander a few seasons were filmed in Paris, they filmed a fight scene on top of the tower once, looked just like that picture in fact.
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