Why do the birds perch on the power line
Everyone knows that if people standing on the ground come into contact with high voltage wires, there is a risk of electric shock. But strangely enough, we often see some birds perched on high voltage electrical wires, after a long chirping of chirping peacefully fly away. Why is the bird not electrocuted?
It’s not that a bird has any special bravery. You see, they are all perched on an electric wire. Their bodies are only in contact with an electric wire, not forming an electric circuit; there is no current flowing through them, so there is no electric shock.
If we stand on the ground, and the body touches the firewire (high voltage wire) in the electric line, it is considered a seamless electrical connection. The current will pass through us and run to the ground. That is an electric shock.
If we wear very reliable insulating rubber shoes or stand on an insulated wooden chair, even touching the firewire with our hands will not receive an electric shock. Then you are like the case of a bird perched on a wire. Some experienced electricians, able to perform operations in the presence of electricity, are familiar with this principle.
Once no current flows, no matter how high the voltage is, there will be no electric shock. Then, why can being near high-voltage lines be dangerous too?
That’s because when a person walks near the high-voltage wire, his body is subjected to high-voltage induction. If the distance is too close, the air layer between the person and the high voltage wire will likely be penetrated. The air, which is a very good insulator, becomes a conductor after being struck through it. So a very strong electric current will flow through the body, causing an electric shock. So don’t get close to high voltage wires!
Besides, do not use wet hands or when a part of the body is soaked in water but touch switches or appliances with electricity. Because under constant voltage conditions, the smaller the resistance, the greater the current produced, the resistance of the human body is basically on the skin. If the hands are dry, it is a few tens of kilograms. If 220 volts are accidentally touched, a strong electric shock may result, but generally not to danger to life. If the hands are wet or part of the body is soaked in water because the water is a good conductor of electricity, the skin’s resistance will be greatly reduced. When touching 220 volts, there is a possibility of electric shock.
When you encounter this situation: if a line is on high voltage, if it is dropped in the car you are in, the car is charged. Since a car tire is a very good insulator, although your body’s voltages and the car are both very high, no current flows through you. Therefore, sitting still in the car is very safe, without electric shock. Remember: don’t get out of the car! Because when you just put your foot on the ground, the electricity in your car will flow through your body to the ground, in your body will generate a very strong electric current, which is dangerous.
To prevent electric shock, do not fly a kite near the power transmission line. High voltage current can be transmitted to your hand by the line; Should not climb electric poles, high voltage can cause death. Don’t try to poke through the socket with your finger once your body is seamlessly electric with current flowing through it; do not come near broken wires. If someone is “sucked” tightly by electricity, they cannot touch them with their hands but must urgently find wooden sticks or dry bamboo sticks to remove the wire. Electricity, as well as fire, is “maid” useful. Just by grasping its law, it can make it serve us better without causing any harm.