October 26, 2008: Electric Fence

[Mayor of Shekou]

Wow. A real field day for that rare person into both bestiality and necrophilia!

[dar512]

I blame the parents. These cows would never have died if they hadn't been grounded.

[glatt]

I understand that in a fence like this, a strong current can be induced during an electrical storm, even if the fence itself isn't struck. When lightning strikes even a few hundred feet away from the fence, it radiates an electromagnetic field, and as that field passes by the fence, a current is induced in the fence wire. The stronger and closer the lightning strike is to the fence, the stronger the current.

This is exactly the same principle an electric generator uses, only a generator uses magnets for a field source instead of a lightning bolt.

[Gravdigr]

Originally Posted by Mayor of Shekou

Wow. A real field day for that rare person into both bestiality and necrophilia!

Jackpot!!! Giggity-giggity-moo!!

Originally Posted by dar512

I blame the parents. These cows would never have died if they hadn't been grounded.

[Elspode]

I wonder if they were medium or well done?

[sweetwater]

This is an especially tragic scene because the grass is actually greener on their side of the fence... for all the good it did them.

[onetrack]

That number has gotta be some kind of record. I recall a number of years ago, that a farmer situated in the high country (Tablelands) of North-Western, New South Wales (the state in which Sydney is the capital), lost 45 cattle to one lightning strike.
He had previously lost another sizeable number of cattle (about 30, I think) some 10-15 years before.
The Tablelands region has areas that record enormous numbers of lightning strikes, in comparison to other areas, and it's all to do with elevation and topography, that assists thunderstorm buildup.

The number of horses struck by lightning is sizeable, too - both when being ridden, and in older times when working the fields.
If thunderstorms are close, and you're riding a horse, it's advisable to dismount and reduce your profile to lower your chances of being struck.

[tw]

Originally Posted by glatt

I understand that in a fence like this, a strong current can be induced during an electrical storm, even if the fence itself isn't struck. When lightning strikes even a few hundred feet away from the fence, it radiates an electromagnetic field, and as that field passes by the fence, a current is induced in the fence wire. The stronger and closer the lightning strike is to the fence, the stronger the current.

Which makes complete sense until we apply numbers.

If a nearby strike could induce currents that high, then devices designed to maximumize those currents would always be destroyed by nearby strikes. How many cell phones and car radios are routinely destroyed by nearby strikes? Zero.

Campers were sleeping near a tree that suffered a direct lightning strike. Those who were sleeping parallel to the tree were unharmed. Those who were sleeping pointed towards the tree were rushed to the emergency room. Follow the current (just like diagnosing hum from a computer). Current was down the tree, through earth, into the campers head, out via his feet, then outward in earth. Best electrical path was the longest distance through campers who were not parallel.

Same applies to four legged animals that are at even greater risk. Common is for a nearby tree to be struck. That current takes a shorter path by rising from earth into a cow's hind legs. Back to earth on fore legs. Path through a cow is the most conductive path which is why a tree struck 30 feet away also electrocutes nearby four legged animals.

What should be located on golf courses? Shacks surrounded by a buried copper wire loop so that lightning currents in earth need not kill by traveling up one leg and down the other. Instead the buried loop makes an electrically shorter path.

Damage from nearby fields is common when myths get promoted as fact. If nearby fields were so deadly, then every nearby baby monitor and smoke detector were also destroyed.

Only fact was that cows were electrocuted. Was a tree just behind the photographer? Currents down that tree and through cows may have been seeking charges located somewhere on the horizon of that picture.

[SPUCK]

Originally Posted by Elspode

I wonder if they were medium or well done?

No no you have it wrong. They are done 4.