After being hit by bird poop, I discovered a "shocking" secret!

Have you ever been hit by bird poop?

I don't accept it, why is it always humans who get electrocuted, but birds standing on wires are fine!!

Birds sitting on power lines is nothing new. Just look up and you can see a five-line music score...

There is a saying that goes like this: Bird's claws have a high insulation level, just like wood and rubber, so the current in the wire cannot be transferred from the bird's claws to the bird's body, so there will be no electric shock.

Is this really the case? Let’s find out

The nature of electric shock

A necessary condition for electric shock is to be part of an electric current loop.

Living organisms are conductors, and the essence of electric shock injury is the heat damage caused by the heat generated when the current flows through the organism. The greater the current, the higher the heat, and the greater the damage.

There are two forms of being part of a current loop (using humans as an example):

Double wire electric shock

When the human body touches two charged objects in the same circuit at the same time, the current flows from one conductor to another, causing electric shock.

Single-wire electric shock

When a person stands on the ground and a part of the body touches any of the three-phase electricity, the current flows into the earth through the body. This is usually an accidental electric shock. The reason why Cao Felipe was electrocuted while flying a kite was because the kite string acted as a conductor, connecting the person standing on the ground and the high-voltage line.

Why are birds safe?

The structure of the human body is similar to that of a bird, both are basically made of water and are conductors.

But because the bird is small, it usually stands on the same wire, not touching the ground, and will not hook two wires at the same time, so it will not form a current loop. Then, another friend asked:

Curious Baby:

Even if the bird does not hold both wires at the same time, will such a high voltage cause a voltage difference between the bird's legs? Will it create a circuit with the bird's body and eventually cause current to flow?

First, there will be a voltage difference, but it is negligible. This is because the bird's short legs span a short distance (5 cm), and the resistance of the transmission wire (which is very conductive) is very small. In such a short distance, the voltage difference is almost negligible, just like a calm lake surface, where there is no height difference and no water flow.

Secondly, since there is a layer of stratum corneum on the bird's feet, it has a certain degree of insulation and its own resistance is relatively large (about 100 ohms).

According to Ohm's law I=U/R, when the voltage is very small and the resistance is large, the current passing through the bird's body is about a few milliamperes, almost zero, and very weak (compared with humans, the human body's safe voltage is 36 volts, the human body's resistance is about 2000 ohms, and the safe limit current is about 18 mA)

Are all birds safe?

The answer is:

NO!!! In fact, not all birds are so lucky, and many are electrocuted to death.

There was a news report that two starlings were showing affection in a park. In the excitement, one of the birds changed its line. At the moment of their kiss, one of its wings was burnt and one of its legs was broken.

It turned out that at the moment their mouths touched, the two small (conductor) birds (bodies) formed an electric current circuit.

When a larger bird stretches its wings and touches other wires or trees, a voltage difference will be generated, and then, nothing will happen...

For example, owls are often in trouble because they are too eager to catch prey.

Do the splits, standing on different wires

Pawn

Standing on the electric wire, pecking at the uninsulated pole with your mouth

Pawn

Perched on the cross arm of a high-voltage power pole

Grinding the nozzle on a live wire with current

Pawn

Pawn

Pawn

…

So, bird claws are as insulators as rubber, which is wrong (✘)

Birds, like humans and most other creatures, can be conductors, at least they are not insulators (✔)

As conductors, we humans should be more honest. PS: The following table shows the safe distance between personnel and energized high-voltage AC lines given in my country's "Electric Power Safety Work Regulations".

Cherish life and stay away from high-voltage lines!

Source: State Grid Jiangsu Electric Power

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