Relation between voltage and current What I know is that voltage is the electrical pressure which is required to drive the electrons in a circuit. According to that we have higher currents when there is a high voltage. Ohm's law confirms that. What I don't understand is that some books say that it is the current that is more dangerous to the human body and not the voltage. What I mean is higher currents are dangerous but high voltages aren't. But if we have a high voltage aren't we indirectly meaning that there is high current since they are directly proportional to each other.
 A: The current you are going to get through your body depends on the voltage and on the resistance. 
You can touch a 110 V exposed cable using a piece of metal or a piece of plastic - in both cases the voltage is the same, but the resulting current - and hence the danger - is greater in the first (metal) case.
A: I always thought this rule of thumb was a bit silly - current kills because it was driven by a voltage, otherwise there would have been no current. 
The rule arises because of the variability of skin resistance. Little voltage applied internally across your heart will kill you, but the skin's variability means that it is impossible to say what external voltage will cause this voltage. 
If we specify the current, however, the problem is sidestepped. A lethal current requires whatever external voltage is needed to drive it. 
A: What kills you is the current not the voltage, as you read on your books.
Of course that you to have a voltage difference so the current can flow, but it does not determine how strong the current will be. I do not know if I would die if I touch something with 1 kV. That's because the current will depend on the sum of the resistance between me and the ground (it will depend if have rubber boots, or gloves, or if I am in the middle of a jump).
What I do know is: no matter the voltage I touched, I will die if 10 Amps pass through me (please do not consider miracles for the sake of the explanation)
