Originally posted by: Calin
Originally posted by: bobdole369
3 ma was the lethal current (at least as we were told in the Navy.
Its not the voltage that kills ya, think of voltage as the pump in a fire truck. If the pump moves faster you can push more water through the same hose. Current is the amount of water going through, so if you increase the voltage you ALSO increase the current. If you reduce the resistance (such that when you puncture the skin), the amount of current that flows for a given voltage increases. Its like putting in a bigger hose. Same pump, bigger hose, more water.
3ma supposedly kills you by interrupting your brains normal process, and supposedly this was demonstrated by inserting needles into the soft part of the temple. 30V pushed 3ma through the brain killing the individual as his heart started to fibrillate. (Dunno why, I thought the heart had a pacemaker) I take that with a grain of salt, as these were Navy instructors not wanting us to become electrocuted.
There is a biological pacemaker, heart is totally independent of brain voluntary control (if you can accelerate your heart beats by your will, please tell me).
The pace maker in the heart can be "affected" by other means (like hormones, adrenaline and so on), and it uses some "chemical ionic" process to know when to "beat". There is a central spot that gives rhytm to everything, but there are many small "parts" of the heart that will "beat" on their own. This is fibrillation - when every small muscle of the heart will "beat" at its own time. It looks like a big band adjusting their instruments. Once the heart is "defibrillated", all the random contraction finish and the beat comes from the single central spot, and the sound is clear and everything work fine.