IANALS (Lightning Specialist)
- Lighting is more or less electricity.
2.Electricty and water dont mix.
3.If they do mix, all things in the body of water die.
So how on earth do we still have fish and other creatures?
Lightning strikes the ocean all the time. But you are talking about a huge amount of H2O, and all of it is grounded. There isn’t enough amperage to cause any damage beyond the immediate vicinity of the strike.
IANAS (scientist) but the first thing that came to my mind is that the effects of electricity spreading through the water would be limited by the salt in the water. Just a theory that came to my mind with little to no evidence or reasoning 
Anyone care to enlighten another interested observer?
duh posted that without realising there were posts explaining ignore me
Lightning does strike the ocean.
Lightning can kill you if you are near enough to the strike zone.
Lightning dissipates over distant.
Lightning strength varies.
Pure water does not conduct electricity.
I’m a loooong way from an expert on lightning. However, lightning strikes the surface because a large charge, usually positive, has built up in a cloud from which rain is falling taking electrons away with the droplets. So a negative charge builds up on the surface and there is a positive charge in the cloud. If the voltage breakdown resistance of the air is exceeded the electrons all zoom up rapidly into the cloud to neutralize the positive charge there, or at least partially neutralize it. That’s a lightning strike. And so very little current exists below the surface of the sea in a lightning strike.
A lightning strike on the ocean at night can be quite impressive.
I don’t know if it’s the dissociation of hydrogen and oxygen and the subsequent recombination (I always thought hydrogen flames were invisible), but the explosion and flash are huge and bright.
Daylight strikes are not nearly as impressive.
Actually, salt water conducts electricity much, much better than fresh water. In fact, very pure water conducts very poorly.
All true statements. But the ocean is not pure water, not by a long shot. Ocean water is quite a nice conductor.
One more time. The conductivity of the water is of minor important. A lightning strike isn’t something that roars down out of the sky and rams into the sea. Rain falling from the cloud carries electrons along with some of the droplets. The negative charges charge accumulates on the surface of the sea and since they came from the cloud, the bottom of the cloud develops a positive charge. The attraction between these masses of charged particles keeps the negative charge on the surface and the positive charge on the bottom of the cloud. Sooner or later there is a rapid transfer of the negative charge from the surface of the sea back up to the cloud. The lightning strike doesn’t penetrate into the sea.
Correct me if I’m wrong, but I think they use a salt water saturated sponge when a person is killed in an electric chair. :eek:
I think ouryL was responding to mza662’s assertion that conductivity is inhibited by salt.
Indeed, they do. (Or did. I don’t think they use the ol’ smokey-seat anymore.)
Don’t wanna hi-jack again, but I’m gonna…
Do you think electrocutioners went through a trial and error thing with different liquids before they latched on to salt water?
Plain water?..nope…Evian?..nope…Pepsi?..noooo…salt water?
YES! Cleetus!..run down to the sea and filla bucket…
IANAFTHBSIAASBL (I AM NOT A FISH THAT HAS BEEN IN AN AREA STRUCK BY LIGHTNING), but I must believe it would not be pleasant.
Electrocution as a method for execution was thoroughly tested on animals. Indeed, Thomas Edison even killed an elephant to demonstrate the horrible dangers of alternating current. Before the verb “electrocute” was invented, he suggested that the elephant had been “Westinghoused.” I think they probably figured out the saltwater sponge trick before they used it on humans.
I am still quite hazy on when and why current becomes dangerous to a human, but just to patch this comment: Edison chose AC for killing to create negative publicity not because it was more dangerous than DC. There appears to be instances where large voltages?/currents?/whatchamacallits of AC can be run through a human body without issue and this was considered one of the selling points of AC.
Electricity is dangrous to a human for two reasons.
First, if you get a shock across the chest at just the right time, you can throw your heart beat out of whack. The way your heart is designed, if it gets into this funky state, it usually won’t get back out of it on its own, so unless someone is standing next to you with a portable defibrulator, you’re in big big trouble. The important thing here is that it takes a very tiny amount of current to be capable of screwing up your heart beat.
Second, when electricity flows through anything that isn’t a superconductor, some of the energy is converted into heat. A common demonstration (that must be done carefully to be safe) is to put a nail in each end of a hot dog and connect a wire from an electrical plug to each nail so you’ve got 120 volts going to the hot dog. When you switch on the power, the hot dog gets cooked in a very short amount of time (less than a minute). To put it in perspective, house current is 120 volts with a maximum current of 15 amps. A typical lightning bolt is a few million volts with a current of a few hundred thousand amps. Because there is so much energy in a lightning bolt, it causes a lot of burn damage even though the duration of the flow of electricity is so short.
AC is more dangerous than DC for two reasons. First, 50 or 60 Hz (commonly used in AC power systems throughout the world) are in a narrow frequency range that the heart seems particularly succeptible to. If you want to screw with your heartbeat, you almost couldn’t pick a better frequency. Second, DC tends to make your muscles contract in one direction, which makes you typically throw yourself off of whatever you just grabbed to get shocked. AC, because the current is alternating, tends to make your muscles more just jiggle, which makes you tend to hold on to whatever just shocked you.
That said, DC is still dangerous, and while it might be marginally safer than AC, I think Edison’s claim that it was the “safe” alternative was a bit exaggerated.
The reason AC became more popular than DC is because of the AC transformer, which is just a couple of coils of wire wound around a common iron core. With a transformer, you can boost voltages on the transmission system very easily and drop them back down again on the load side. Transformers can’t defy physics, so the power in and the power out of a transformer have to be equal. If the voltage goes up, the current has to go down by the same factor. This is important, because in power transmission, the losses are related to the amount of current flowing, not the power flowing, so if you can increase the voltage as high as you can, you greatly reduce the current, and greatly reduce the losses in the system. You also greatly reduce the size of the wires needed, which becomes really important in a power system where you need miles and miles of wires.
There is no simple DC equivalent of a transformer, which made Edison’s system hugely inefficient and costly for anything larger than a single city block.
There’s a little bit of Hollywood exagerration in this. If someone drops a toaster in a bathtub, it’s quite easy for the person in the bathtub to end up dead, but it’s not guaranteed. I’ve heard of someone wading through a swimming pool where a light on the side of the pool (under the water) had been wired incorrectly. They felt a “tingling” sensation as they got closer to the light, but it’s not like the Hollywood version where everyone in the pool instantly dies.
I can testify to that. Back in the tube days (Hey, I’m old) I tangled with B+ (about 450vdc) more than once and it hurts. It’s more of a ‘pulse’ than a ‘buzz’ like you get off of 60Hz, and I can easily imagine paralyzing your heart or diaphragm muscles, not to mention throwing you into something possibly sharp or dangerous. Nothing you want to play with intentionally.
DD