2 ms·

I was always taught “volts jolt; mills kill”. i.e. high voltage will knock you across the room but a few milliamps of current across the heart will easily kill

• askvictor 7y ago
  But voltage is what matters to pass through the skin. 12v can kill if it's applied below the skin into the highly conductive inside of the body. But to get through skin you need at least 30v.
• eemil 7y ago
  So much misinformation in this thread. Voltage, current, and resistance are physical properties entirely dependent on each other -- increasing one affects the value of others. That's like saying that the mass of bullets kills people, without any regard for velocity. A 12 V car battery can kill you, if it has a low-resistance path that goes through your heart. Touching the terminals will do nothing. Maybe if you applied that voltage to conductive spikes inserted into specific points of the body, there would be some effect. A voltage source, like a car battery, does not determine how much current passes through a circuit. That is determined by the circuit's resistance, and the source's upper limits (i.e. internal resistance for batteries, rated current for power supplies). As voltage increases, so does current. High-voltage supplies will absolutely kill you, as long as they're able to supply the required current. Which, to harm a human heart, is quite low (tens to hundreds of milliamps). Aside from fringe sources like static electricity and tasers, most HV sources are entirely capable.