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Statically Charged Man Ignites Office
Call Me Black Cloud writes "And you think your coworker with BO is annoying? In this story carried by Reuters, a man wearing a nylon jacket over a wool shirt built up such a static charge that he left a trail of scorched carpet and melted plastic in his wake. After he melted plastic in his car he sought help from firefighters called to the scene, who measured his static field at 40,000 volts." Obviously, despite the fact that this is carried by Reuters, you should take some of the 'facts' presented here with some NaCl.
future Mythbusters in the works...
In fact, I'm pretty sure I saw an episode of Mythbusters that covered a similar urban legend. They were able to generate a potentially injurous amount of electricity from static but the size of the apparatus they built had to be huge to pull it off.
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Electrical field is measured in Volts, and the description is correct. The potential difference between ground and the man's jacket was 40000V.
Isn't the idea of static discharge that it discharges? Shouldn't lighting up the carpet deplete his jacket, or at least touching his desk, keyboard, door knob, or car? The average static shock is like 10,000v. 40,000 would be painful, but not something you would remember THAT long.
More detail here. Apparently an ABC journalist verified that there were burn marks on the carpet.
:wq
They mention "volts running through X" in several places (which makes no sense because voltage is like pressure; it does not move). They mention voltage (a different number than in the other article) but nothing about how that could result in burns.
:) Similarly, static electricity sounds scary because it easily runs in the thousands of volts... but the voltage is not refreshed. Once it is discharged it is gone. And discharge at that voltage happens by leakage in the air, through his feet, etc. It could not create temperatures that high over that large an area.
:p
You actually create insanely hot temperatures when you scuff your feet on a floor. You do melt the carpet doing that, but only the top few layers of molecules
Another way to look at is is where is this energy coming from? Movement of his arms while he walks. Just how much energy is in the movement of your arms? Not a lot. If this were true he should be tied down and forced to create electricity for a small city. Converting food to electricity with his magical clothes would be so cheap compared to any other power source.
"perhaps SHC is therefore no longer a mystery?"
The Discovery Channel or TLC had at least a show on this, the most common was the 'wick effect.' It's normal combustion that is limited to the body, usually happens when someone is knocked unconscious or dies while holding a cigarette or candle. I don't think this case would be considered spontaneous combustion since the build up of static electricity is an ignition source, then it's normal combustion once the fuel reaches its flash point.
F7 doesn't work, ignore spelling and grammar
To elaborate on what the parent poster said, assume the capacitance of the human body is 10 pF (see http://en.wikipedia.org/wiki/Capacitor). Using the equation: E = 0.5*C*V^2, a potential difference of 40kV only gives a maximum of 0.016 Joule of energy. That's not a lot of energy. Assuming the discharge happens over 1 millisecond, this would result in a power of 16 Watt, which is obviously insufficient to ignite someone.
Unless the person was standing in a convenient fuel-air mixture, it is unlikely they spontaneously combusted due to electrostatic discharge.
Had a special where they debunked Spontaneous Human combustion. One plausible theory seemed to be the "human wick" theory. Basicly you fall asleep smoking, the cloth/clothes around you catch fire, you are knocked unconcious by the fumes, the clothes act as a wick burning up the fat in your body, often only the legs remain due to less fat an no cloth on them (old ladies are frequent wictims to this) Also, bones burn due to the fact that a lot of the old ladies have ostoperosis.
A computer is a tool, but I am not. I use Linux
Building heating systems produce lots of warm dry air creating a static friendly environment.
I had a similar experience back in HS, the letter sweaters were made of 100% acrylic, I don't know why they were, but they were. At the end of every day it was go down to the locker room and take the sweater off, the popping sound was very audible, and discharge by grabing the door or hit some random freshman walking by.
F7 doesn't work, ignore spelling and grammar
40,000 would be painful, but not something you would remember THAT long.
You won't feel the voltage, but the current. The voltage is what makes it happen. You won't get an amp of current flowing through your skin at 10 volts, but you will if 10,000 volts is sustained. Once the voltage is applied, current will have to wait a fraction of a second to overcome inductance, then it would have an open highway. Once the path of current has been established, its likely the source of energy has been dishcarged and dropping the voltage down to an insignificant amount. Its the milliamps that will kill or start a fire.
Unless of course you are discharging an infinite energy source such as a 14,440 volt power main off the neighborhood telephone pole, which the constant voltage source will supply the steady current needed to form conductive carbon trails that will burn themselves through the body, superheat tissues, and cause limbs and organs to explode like sticks of dynamite.
..becuase most of us outside AU haven't heard of Warrnambool, but we have heard of sydney.
If you read the news around here, *everything* that happens in AU happens in sydney.
The Reuters article is a particularly bad piece of journalism though.. confusing volts and amps, inserting the 'rubbing clouds' quote, and even getting the facts wrong (it was 30kv not 40kv).
Note that the original story, not the ignorant rewrite on rueters mentions only 30,000 volts and a mention of amps at the end. And in Australia, they are in late winter, this being the southern hemisphere.
So plenty of potential for walking leyden jars. Obviously this all is unpossible. Modern science tells us so.
Original Story
Freak static
By SARAH SCOPELIANOS
September 16, 2005
A DENNINGTON man was none the worse for wear yesterday despite having 30,000 volts running through his clothes.
Warrnambool firefighters were baffled after Dennington cleaner Frank Clewer unintentionally caused three Koroit Street buildings to be evacuated.
Last night fire officers said they remained puzzled about the incident in which carpet was scorched where Mr Clewer had walked.
Mr Clewer, 58, was jovial about his fiery experience but said the circumstances were hard to believe.
Soon to be made redundant from Nestle, he had arrived for a job interview that never quiet started.
He could only chuckle about the events which led to firefighters stripping him of his clothes and finding 30,000 volts running through his synthetic jacket.
"My wife has told me I'm not allowed to put on the electric blanket tonight and I'm going to have to lay off the surfing because I'll stun the sharks and we'll have fried flake in the bay," he laughed.
Fire crews were called to Karingal's office yesterday after staff heard loud cracking sounds and noticed the carpet was burnt in several places.
The "seriously weird" events began when Mr Clewer was standing at the office front counter when he heard a "mighty crack" before being led into a room to begin an interview for a carer's job.
Then staff noticed burn marks the size of ten cent pieces on the carpet and called the fire brigade.
Fire officers' investigations included removing carpet and evacuating surrounding buildings.
Mr Clewer spoke with them for about 20 minutes then went to the bank and a surf store before returning to his car at the Ozone car park.
There he found that a plastic bag used to protect his seat from water after surfing was badly charred beneath his feet.
Thinking staff at Karingal were experiencing the same "strange" happenings, which included electric zapping sounds, he returned to the Koroit Street building to consult fire officers.
"I was talking to them and I let out a crack. It is all too bizarre...and when I was getting inside my car after giving them my name and phone number, I let out another almighty crack and it was heard inside the building by the fire officers and inside the ABC studio."
Mr Clewer was given overalls to wear as fire officers used a device to check static electricity on him and his belongings.
The device measured a remarkable 30,000 volts on a synthetic zip-up jacket Mr Clewer had been wearing under a woollen jacket.
His jeans had a small burn at the knee.
Warrnambool fire officer Trevor Roberts said officers were baffled.
"We called Powercor, an electrician, and spoke to a technician from the ABC."
He said Mr Clewer's clothes were at no stage dangerous because they were low in amps which could be deadly.
This story was found at:
http://the.standard.net.au/articles/2005/09/16/112 6750111141.html
"It is a greater offense to steal men's labor, than their clothes"
Really? I wanted to get into Reuters and chatting to one of their senior London subeditors. To get in, you need to know more than one language (preferably something other than French and German, as that's common now), pass standard journalism tests and hold any degree. Hell, I have an engineering degree. Think about it. Reuters sells news around the world to media outlets and companies. It's, commercially speaking, not in their interest to sell slanted news - because if they're biased, they'll drive away people who are sympathetic to whichever cause is being bashed.