3 ms·

I've always struggled to grok electricity - why not? Isn't this 120V straight through you to the ground?

• joecool1029 5y ago
  No, skin is fairly resistant unless punctured or covered in water. This is why building codes usually only mandate ground fault detecting outlets in areas where water is expected to be (outdoors and bathrooms). For further reading, go research how electric chair executions had to be performed and how prone they were to failure due to not passing a fatal current.
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• KMnO4 5y ago
  Something I always tell my students: current is pulled, not pushed. According to Ohm’s law, I = V/R. The resistance of your skin is constant (well mostly — you can of course get it wet to decrease resistance), so the only way to increase the current is to increase the voltage. Same thing with car batteries. People are always scared because 800A is flowing through the wires when you’re starting a car. If those batteries are capable of 800A then surely you shouldn’t touch them. But at 12V, you’d need a resistance of 0.015 Ohms to get 800A. If your dry skin has a resistance of 100kOhm, the most current flowing through your body will be around 0.1 mA.