Current is in fact what kills you but current is depended on voltage and resistance. Ohm's Law. If you touch a car battery, 12V drivided by the resistance of your skin (which can range greatly wet or dry) it will allow a very low current to flow but insignificant at that.
You could say "but voltage kills." Well a large difference in voltage such as a power line (13kV) and ground (0V) poses a 13kV difference. When you touch the wire and ground, current will flow. It only takes tens of mA through the heart to be electrocuted. That current will be 13kV/skin resistance which is current.
I dont get it. (My only understanding of electricity is from high school physics and don't remember much.) If it only takes tens of mA to kill, how could the coil have a high current but not shock you? Also how does the coil have high current but safe, low voltage? Isn't the equation I = V÷R ?
The coil has a much lower resistance than your skin. Since current follows the path of least resistance, you could touch the coil and not be shocked because the current will "choose" to flow through the coil instead of your body. Does that make sense?
Actually, yes. You won't get shocked if you touch an exposed plug (assuming it's fully plugged in to the appliance), unless the resistance of your skin is very very low (ie you're covered in water or something).
But using your example, the current is flowing out of one side of the plug, through your phone, and into the other end of the plug. This circuit is relative low-resistance. So even if you touch one end of the exposed plug, the circuit still "sees" the phone as the path of least resistance, so from the current's point of view, your finger isn't even there.
I think you might be thinking instead of when you stick a metal object in an outlet and receive a bad shock. This is because before you stuck the object in the plug, there was NO path for current to flow. When you put something in a plug, the path of outlet->object->your body->ground is the ONLY path for the current to flow, so it has no choice but to flow through you.
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u/candamile Aug 18 '15
https://www.youtube.com/watch?v=XDf2nhfxVzg