2006-10-04 03:33:21 · 9 answers · asked by leelee 1 in Science & Mathematics ➔ Engineering
There is no potential difference between their feet. In other words, no current flows through them. It is the current that kills and the high voltage causing a large potential difference that causes a current to flow through a body, but since both legs of the bird are on the same wire with no potential difference between the two points on that wire, no current flows through the bird. Think of it as a short circuit. The electricity would flow through the wire instead of trying to flow through the bird which has higher resistance.
2006-10-04 03:41:14 · answer #1 · answered by lkraie 5 · 2⤊ 3⤋
When the bird perches on a live wire, her body becomes charged--for the moment, it's at the same voltage as the wire. But no current flows into her body. A body is a poor conductor compared to copper wire, so there's no reason for electrons to take a detour through the bird. More importantly, electrons current flow from a region of high voltage to one of low voltage. The drifting current, in effect, ignores the bird.
But if a bird (or a power line worker) accidentally touches an electrical "ground" while in contact with the high-voltage wire, she completes an electrical circuit. A ground is a region of approximately zero voltage. The earth, and anything touching it that can conduct current, is the ground.
2006-10-04 10:42:06 · answer #2 · answered by Jemima 3 · 2⤊ 1⤋
Because they are not grounded. When they perch on a high transmission line they become part of the circuit. And since they are not grounded (touching earth) the electricity just passes through them. It holds the same for humans (except humans wear protective gear to prevent contact with the line if they perspire. perspiration acts like a ground). As long as you do not touch ground you will be safe. How do you think all the technicians repair lines when they are live.
2006-10-04 10:43:00 · answer #3 · answered by KC2EGL 2 · 2⤊ 1⤋
The transmission lines are separated by space and air. As long as the bird doesn't touch another wire or ground it is perfectly safe. They perch on 250K VAC lines with complete safety as well. The power is transmitted via three phase conducting wires. You probably noticed that there are three power lines on each tower and are supported on the towers by insulators.
2006-10-04 10:42:40 · answer #4 · answered by FrogDog 4 · 1⤊ 2⤋
Same reason as why Electrical Engineers place crushed rock as the ground in Electrical Substations
Potential Separation and Isolation ensures no current flow and potential difference between legs.
2006-10-04 10:52:20 · answer #5 · answered by Anonymous · 2⤊ 2⤋
Electric current is not passed through the bird because there is no earthing.
2006-10-04 10:41:17 · answer #6 · answered by Pitambri 3 · 2⤊ 1⤋
because they perch in the neutral line.
2006-10-04 13:33:46 · answer #7 · answered by The Apostle 2 · 0⤊ 1⤋
Because they would have to be touching both lines to get electrocuted.
2006-10-04 10:41:05 · answer #8 · answered by crazycatlady 2 · 1⤊ 3⤋
i think it wont harm u unless your grounded,then your toast.
2006-10-04 10:41:29 · answer #9 · answered by forest lover 2 · 2⤊ 1⤋