Why do birds don't die when they lay in high voltage poles?

Answer 1

it's not the voltage in one line that kills when you touch it, but the difference in voltage between the lines.. birds are usually small enough that they don't touch two lines at the time, so there is no differential and it's harmless to them...

Answer 2

Electricity requires a different potential to the one that its at. Voltage is otherwise known as a potential difference. The potential difference between a High Voltage line and the earth (ground) is usually 33,000 Volts. When the bird sits on the line its potential is also 33,000 volts, therefore their is no potential difference, so no current will flow through the bird. So the bird is unaffected by the voltage potential it is at. Should the bird be in contact with the ground and the line, their would be a potential difference of 33,000 volts, which would flow through the bird, and all the current (AMPS) that come with it. Should this ever occur, this will heat the bird up to the point where it is vapourised as the bird does not cause enough resistance (ohms) to draw enough current (amps) to trip the circuit protection.

Answer 3

There will be a minimum of two lines, one is called phase and the other is called neutral. Some times one is phase and the other is earthed (grounded).

There is a potential difference between the phase and neutral.

The neutral and ground can be taken to be at zero potential and the phase is at high potential.

If the potential difference between the two which are separated by a distance of 1 cm is more than 30 kilo volt then the air between them breaks down and will conduct current (charges flow).

Generally the phase and neutral are separated by more than 50 cm and the potential difference is well less than 30 kV.

Hence, when the bird sits on one wire say Phase then it is having high potential but no charge flows through the body. If some how, it can touch the other wire (neutral or the ground wire) charge will flow through it making it fatal.

Answer 4

I have pulled off many dead animals from high voltage power lines, most of them die because they make contact with the return wire ,earth or another phase, it is also possible for them to die if they are struck by lightning, but while they sit on a single wire they are semi safe. mostly high voltage will travel over the surface of a bird or animal and into the air (which is a poor conductor at lower voltages) so therefore does not damage vital tissue, it is only when the voltage is high enough to break down the resistance of the skin and allow a damaging current to flow through vital tissue that it will kill. It is the current that damages and is capable of stopping the heart from beating, the current in a 1.5v AA battery is enough to stop your heart from beating and damage vital tissue! but because the voltage is so low it cant break down the resistance of your skin once again you are safe. Voltage and current behave in odd ways so there is no simple explanation for what it does.

Answer 5

They are not completing a circuit. By this I mean, they are on a high voltage wire but not making connection to a low voltage wire, IE: a ground. The reason you would die doing the same thing is because you would be standing on the ground or if you were up the pole, your size would cause you to touch the pole itself, another ground connection. Do not try to prove my point.
Vaya con DIOS

Answer 6

Two reasons:

1. The cables are often insulated.
2. Even if the cables are uninsulated, a bird will only be touching one cable at a time, and nothing else. Therefore there is nowhere for the current to go to by passing through the bird, so no current flows.

It is current flow, not voltage, that does harm.

Answer 7

By being on only one line, they are not completing a circuit cause they are not grounded. So, the electricity will not flow through them or electrocute them. Now, if they land too close to say the main pole holding up the wire, or two birds on two different wires were to stretch and get close enough, there would be a ZAP as the both got fried.

Answer 8

Because they would need a voltage to pass across them. If the birds sit on on a conductor there is no where for the electricity to go! It is all down to the potential of the bird, If you could fly, with a earthed cable in your hand, and went near the bird you would fry it!

Answer 9

Technically the bird would be dead the way your question is phrased. Poles being vertical structures set in the ground if it was a high voltage one I reckon you would have a chicken kebab as soon as you turned on the power.

Answer 10

because the potential difference between the 2 points the bird is standing is the same(cos the poles hav vv low resistance). hence no current will travel through the bird and kill it. u dun die when u touch sth with electricity. u die only when electricity travels through you. Now take another example of a man standing on the ground touching the pole, since there is a potential difference between the 2 points of contact( his foot with the ground and his hand with the pole) electricity will travel through him into the ground, killing him..

Answer 11

In order for electricity to kill you, there needs to be a path to the ground (This is why lightning likes to strike the ground).

In theory, you could jump out of a plane, grab an electric line, and hang there quiet safely, because you are not connecting with the ground. Theory yes, But not one I am interested in testing.

The other danger is completing a circuit between 2 cables, as the electricity will flow through you to get to the other cable. You have just created a parrallel circuit, so the electricity will go both ways, through you)