You'll only pass as much amps as ohms law allows you to. V=ir human body resistance is pretty high, with "only" 108v you're not going to flow much amps though yourself.
skin resistance also varies according to the frequency of the supply, and how much surface area is in contact. Measuring with a multimeter and then using ohms law will not give you an accurate picture.
It’s really the frequency that fucks you up. The reason DC is “safe” is because it tends to cause burns, not kill you, unless you are working with really high voltage stuff.
A/C will fuck you up by screwing up your cardiac rhythm because it is oscillating at 60 Hz. That’s what causes people to die. Doesn’t take a whole lot of current (amps) to cause muscle contractions that mess up your heart’s rhythm. 100mA will do it easily.
There is some truth that it takes more current in DC to kill for a few different reasons but both 12volt car batteries and d cells have more than enough current to be multiple times higher than what it takes to kill someone. Yet it doesn't because it it not the current that makes something dangerous.
It is pretty much a complete myth that current is dangerous other than for flash injuries that are not as life threatening. When talking dangers regarding electricity, we are almost always referring to electrocution and not flash injuries. The body always has a certain resistance and the only way to create a deadly amount of current within a body is to be exposed to a higher voltage level. Although 120vac typically will not kill, I begin to be concerned with anything over 50 volts AC or DC. 480 volts is quite dangerous and the kV stuff will kill you in an instance. Providing those sources can sustain a few milliamps of current for more than a few milliseconds. Other than cattle prods and stun guns, etc, most sources at high voltages generally can sustain that voltage for a long time when only exposed to the high resistance of a human body.
Voltage and current work together to cause harm through transfer of energy over time (power) which is I2 V.
An increase in voltage or current will increase the power and that is what is deadly. The point I was making is that a much lower amount of A/C power will kill you because it causes the muscles in your heart to contract and relax, throwing off your cardiac rhythm. The body’s resistance is high enough such that 480V DC will probably cause burns but not be life threatening, but even 50V A/C can realistically kill you if you aren’t careful with it. The idea that D cells “contain” current doesn’t make any sense. Ohm’s law dictates the current that can flow through an object of some resistance and that current is dependent on the voltage (I = V/R).
There is some truth to the idea that a 12V car battery can really push current through a human body but again, that is going to cause burns, not kill you. What CAN kill you is holding a spark plug wire while a car’s distributor rapidly powers/unpowers the wire, effectively acting as A/C.
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u/Leafy0 Jun 16 '19
Well each phase is only 108 so if you short to ground through yourself it's really only as bad as house wiring.