Geek研究: 為什么鳥(niǎo)兒站在高壓電線(xiàn)上卻沒(méi)有被電擊？

It's not unusual to see rows of birds perched on power lines. But did you ever wonder why birds aren't electrocuted by the enormous currents that flow through these high-voltage wires? You might think it's because the wires are insulated, but they're actually not insulated at all — that's why downed power lines are so dangerous. No, the only reason why birds on power lines usually aren't electrocuted is because the wire is the only thing they're touching! Like all energy, electricity seeks equilibrium, or balance. That means electricity will flow from high-energy areas to areas of less energy, always using the path of least resistance. So if the bird has one foot on our original wire, and the other foot on, for example, the ground or on a different wire with less voltage, the bird would be electrocuted. Because the electricity would pass through the bird on its way from the high-voltage line to the lower-voltage line or the ground. But as long as both of the bird's feet are on the same wire (or wires of the same voltage), the bird is safe. The current doesn't have anywhere else to go, so the electricity won't pass through the bird–it stays on the path of least resistance, the wire.