I would not want to be under 180 Km of wire falling at 32 feet per second squared.-Job- said:I'd say, if the speed of sound in a rope at some temperature is S m/s, then the other end of the rope wouldn't start to come down until the sound wave got there. So if the rope has length L meters, then it would take at least L/S seconds for the rope to start coming down. Of course because a rope stretches, and even if this stretching is very minimal, if the rope is very long, in a fair amount of time it will have stretched significantly, so my end would come down a bit. If it were a wire instead of a rope, then this probably wouldn't be significant. If the speed of sound in the wire is anywhere around 300 m/s then, in order for me to hang from the ground for 10 minutes, i would need a wire of about 10(60)300 = 180 Km.