Quote: "It's not volts that kill you it's the damn amps, so why do they have high voltage signs?"
Let me try and explain, you are correct that the amps kill you, not the volts. However, without significant voltage to deliver the amps through your body's internal resistance, you really aren't in any danger.
For example, I just measured the resistance from one hand to the other, and the meter read 100k ohms. I=V/R (current equals voltage dived by resistance), so you grab a car battery (which has the ability to deliver hundreds of amps): I=12/100000, current equals 0.00012 amps. It takes .0075 amps through the heart to kill you, and since .00012 is less than .0075, it doesn't kill you.
Now grab 240 volt mains power. I=V/R, I=240/100000, I=0.0024, 0.0024<0.0075, so you still havn't reached the death threshold. However, when you get into the 0.0030 amp range, your muscles begin to act on the current, meaning you may not be able to let go of the current source, as your muscles will involuntarily contract.
Now let's introduce another factor: dampness of the skin. I just licked my fingers and the meter read 40k ohms. Let's grab the 240 volt mains again. I=V/R, I=240/40000, I=0.006, 0.006<0.0075, but now you are really pushing the limit and may actually die if you are female (females typically only need 50ma to be killed). At this point, you will be experiencing severe pain, difficulty breathing, and you won't be able to let go. Extended exposure could cause death.
Now grab the high voltage line on the utility pole outside while being grounded. In the US, a neighborhood-level distribution line is around 7200 volts. I=V/R, I=7200/100000 (we'll assume you're dry), I=0.072, 0.072>0.0075, that's 10 times the lethal dosage, you're toasted.
Now, let's take a look at a tesla coil. These machines can generate millions of volts, but only very small amounts of current, so without the current capacity, your body just disapates the voltage, and with voltage disapation, the tiny current that is produced doesn't make it far enough into your body to stop your heart. This of course depends on many factors, and some tesla coils may be able to kill you while other may not, depends on their construction.
If you've ever wondered how somebody can get struck by lightning and survive, it's b/c of the "skin" effect. Very high voltages travel outside the conductor (which is why high-tension power lines are so small, they only need provide a path, the electricity kinda "floats" along the outside of the wire), so when somebody gets hit by lightning, most of the juice flows just outside their body (if they are lucky). If they are unlucky and they happen to be in a certain position, the electricity may desire to travel through the body core or extremeties and do massive and/or fatal damage.
Don't try this at home.
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Windows Vista: Just say no.
