Texas flooding how are people not getting shocked

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drcampbell said:
Um, no. Electricity travels along all parallel paths simultaneously, the current in each path being inversely proportional to the path's impedance.
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Maybe the old saw should be simply revised to "Most electricity follows the path of least resistance."
 
ggunn said:
In a related story...

Many years ago when dinosaurs walked the Earth I was in a frat at LSU, and the Greek system there had this massive party every year called "South Seas Island Weekend" where all the frat houses built elaborate sets (like theatre sets) in their yards. A common feature in these sets was some sort of pond made out of sheets of Visqueen surrounded by bales of hay. The house next to ours had such a pond spanned by a rope bridge with structures at the ends made of 2X4's. During the last minute pre-party clearing of tools and scrap from the site, a guy standing knee deep in their pond reached over and picked up a circular saw (the old type made with a metal shell) that was lying on the hay bale next to it. He was electrocuted.
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Many years ago when I was a young dinosaur walking the earth and being in the construction field we had one of the first power saws, a Skil model 77. Many people marveled at it as they had not seen an electric hand held saw before. These were notorious for the hot conductor being being in contact with the metal case. I received many a shock from that. It taught me in a hurry to not touch anything well grounded such as the plumbing drain pipes, all of which back in the days of young dinosaurs were cast iron. Touching one gave quite a shock, and many other young dinosaurs failed to survive those. I am of the lucky ones that part of the path was not through the heart.

And OK, I ought to have said MOST electricity takes the path of least resistance, but the former is how it is usually stated. And I did say it takes only a minute amount passing through the heart to put the heart in arrhythmia . But I figured that not most of you, if not all of you would understand what was meant.
 
Dinasaur said:
As you all well know, electricity takes the path of least resistance.
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electricity takes all possible paths, paths of lesser resistance carry more of the current though.

With all other conditions being the same, salt water has higher conductivity, so voltage gradient zones within the water are larger and a person in that water needs to reach further then they would in fresh water to expose themselves to same voltage level.
 
Dinasaur said:
As you all well know, electricity takes the path of least resistance.
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well, it takes ALL paths to ground.

the current divides according to ohm's law.
sorta prorates the shock value.

and i've seen transformers in substructures under water,
and a phase is going to ground, and boils the water,
until it boils enough away it's not a path anymore.
if the resistance is low enough, it'll relay. if it's not,
it'll make cup-0-soup for a week, until it drys things out.
 
Fulthrotl said:
well, it takes ALL paths to ground.

the current divides according to ohm's law.
sorta prorates the shock value.

and i've seen transformers in substructures under water,
and a phase is going to ground, and boils the water,
until it boils enough away it's not a path anymore.
if the resistance is low enough, it'll relay. if it's not,
it'll make cup-0-soup for a week, until it drys things out.
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That strikes me as just terrifying to watch.
 
Dinasaur said:
... I ought to have said MOST electricity takes the path of least resistance, but the former is how it is usually stated. And I did say it takes only a minute amount passing through the heart to put the heart in arrhythmia . But I figured that not most of you, if not all of you would understand what was meant.
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I'm not just nitpicking. I think it's important to challenge "path of least resistance" because there's a widespread misunderstanding that a person is not at risk so long as there's a better path nearby. And yes, everybody here understands Ohm's and Kirchhoff's laws; people who don't read electrical bulletin boards are more likely to make that mistake.
 
Dennis Alwon said:
I am certain those areas are shut down however even if some areas are underwater and have some live circuits there would have to be unusual circumstances to get shocked. Water may be conductive with the impurities however it still has a high resistance so you would have to be in close proximity and touching something that would be at a different potential.

I am sure others can do a better job explaining
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AC also behaves very differently and can get through things much more than resistance suggests. You'll get a very high resistance if you trap water in a small tube and measure across the ends. If you parallel a million 100Mohm resistors, it will be 100 ohms.

Even if you have a hull that is coated perfectly flawless, something like a metal hull has a very low AC impedance since you have a metal with a bunch of microscopic flaws covered in a dielectric and millions of high resistance resistors conforming to the outside. AC passes through as if insulation didn't exist by capacitance. The dock / ship can both be a collector for the ground or a conductor. A submersed line can couple through water and capacitance and the large surface area of hull would act as a collector. Nothing a GFCI can do about current flow from different ground potential.
 
mbrooke said:
Another tragic incident involving electricity :(:(:(:(:(:(

http://www.cnn.com/videos/us/2017/09/01/rescue-team-electrocution-pkg-kaye-ac360.cnn
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[/begin tirade mode]
It's a pet peeve of mine when journalists use the language incorrectly. They should know better and what's worse people hear these incorrect usages and repeat them. In the video she says " the men were electrocuted several times." Obviously, since electrocution is death by electrical shock, you can only be electrocuted once, however you can be shocked multiple times. I also find the use of "flounder" instead of "founder" annoying.
[/end]
 
Coppersmith said:
[/begin tirade mode]
It's a pet peeve of mine when journalists use the language incorrectly. They should know better and what's worse people hear these incorrect usages and repeat them. In the video she says " the men were electrocuted several times." Obviously, since electrocution is death by electrical shock, you can only be electrocuted once, however you can be shocked multiple times. I also find the use of "flounder" instead of "founder" annoying.
[/end]
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Even more when I am on forums or chatrooms and I tell people "hey, the media is incorrect in the use of X term" only to get followed by 20 comments about why the term is correct and I am not because everyone they knew used it that way- me looking dumb as ever :roll::rant: But there is a reason why its called fake news. Its to bait and sell ads at any cost. And as one of my teachers put it: "the media is deliberately written to convey information at about an 8th grade reading level. Its the lowest academic level one can legally complete a diploma outside of special education" When one thinks about it it makes sense in terms of informing the lowest common denominator. But still- there are times when I see information incorrect for any grade level simplified or not. I believe J.K.Rowling more in regards to reality then I do CNN.
 
Coppersmith said:
[/begin tirade mode]
It's a pet peeve of mine when journalists use the language incorrectly. They should know better and what's worse people hear these incorrect usages and repeat them. In the video she says " the men were electrocuted several times." Obviously, since electrocution is death by electrical shock, you can only be electrocuted once, however you can be shocked multiple times. I also find the use of "flounder" instead of "founder" annoying.
[/end]
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Years ago in my early days in the semiconductor business, an article came out in a trade magazine where the writer was attempting to describe the difference between static and dynamic RAM (computer memory). He wrote that the difference was that dynamic RAM had to be refreshed periodically (true) and the refreshing was accomplished by positioning a fan over the memory chips and blowing cool air over them (untrue to the point of hilarity). Copies of the article with that passage highlighted were tacked up on bulletin boards all over the office.
 
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