When is it safe for electric current to pass through the body, and when is it dangerous?
I don’t mean quantity of voltage; I mean that is it dangerous if I were to hang from a live wire (aka not grounded), or if I am grounded is that dangerous? Is it possible to have electric current flowing through the body safely, then instantly die because you touch a ground/stop touching a ground?
In: Physics
Birds can stand on power lines and be fine because they are not grounded. A small amount of current will go through their legs as they form a parallel branch, but the resistance of this path is so much higher that only a tiny tiny fraction of the total current will go through their legs. Similarly, if you just hang from a live wire there won’t be enough of a voltage difference across you for any meaningful amount of current to flow. But the second you touch ground, you will form a direct path from high to low voltage and current will flow through you. This current will cause your heart to spasm and cramp if it flows through it, and at high enough currents you will experience internal burns. If you’re close enough to a path to ground but not touching it, you can have a current flow through you and arc to that ground, or you can act as a capacitor and have current flow in and out of you with the alternating current. It is never safe to have current flow through you except in very small amounts.
[Here’s a video of linemen climbing on a high voltage transmission line.](https://youtu.be/9tzga6qAaBA?si=Mi1H-WtAhly-aCKl) They have to be placed on it with a helicopter to avoid ever being close to a path to ground and they wear clothes made with metal fibers so that current flows around them rather than through them.
Latest Answers