why do squirrels not get electrocuted on power lines
How do birds sit on high-voltage power lines without getting electrocuted? YouБve probably never seen a bird straddle two wires at once, and thereБs a good reason for thatБ
By Aaron Johnson ItБs not uncommon for a character in the movies to end up with a blackened face and a headful of frizzy hair after touching a live electrical wire. What makes for a good gag in the entertainment biz, however, is likely to kill you in real life Б unless youБre a bird. Birds have no problem sitting, unruffled, on the high-voltage power lines you often see lining the road. This ability has nothing to do with them being birds, explains Ranbel Sun, a recent grad from electrical engineering and computer science who currently teaches at Phillips Academy in Andover, Massachusetts. ItБs all about the connections theyБre making Б or, more importantly, not making. б БElectrical current is the movement of electrons,Б explains Sun. The movement of electrons through a device like your TV is what gives it the energy to display images and produce sound. Sun describes the long process these moving electrons take to get to your house. БThe electrons are essentially being pulled from the ground by the power station,Б she says. БThey move through the power lines, through your TV, and eventually they make their way back into the ground from where they came. Б This creates a closed loop, which is required for electricity to flow. б б The other thing electrons need in order to move is motivation Бб or, more specifically, a difference in whatБs called electrical potential.
БImagine lugging a bunch of bowling balls up a mountain,Б Sun explains. БIf you give them a path, the balls will naturally roll down the mountain to a lower position. Б At the top of the mountain, the bowling balls (which represent the electric current) have a high potential, and they will travel down any path that becomes available. When a bird is perched on a single wire, its two feet are at the same electrical potential, so the electrons in the wires have no motivation to travel through the birdБs body. б No moving electrons means no electric current. Our bird is safe, for the moment anywayБ If that bird stretches out a wing or a leg and touches a second wire, especially one with a different electrical potential, it will open a path for the electrons Б right through the birdБs body. б б There are other perils for our feathered friends, Sun points out. БThe wood pole supporting the wires is buried deep in the ground,Б she says, Бso it would also be dangerous for a bird to sit on the pole and touch a wire. Б This is the problem that people encounter if they touch live wires Б since we are almost always in contact with the ground. Our bodies turn out to be excellent conductors of electricity, and the electrical current will happily use them to complete a closed path to flow from high potential (the wire) to low potential (the ground).
ZAP! б So how do workers repair live electrical wires without getting hurt? They use insulating materials in their clothing, equipment, and bucket trucks. Insulating materials such as rubber are materials through which electricity has a hard time flowing. So instead of passing through the electrician, the electrons stay on the other side of his rubber gloves or rubber-handled tools. (Keep in mind: these arenБt everyday household gloves and tools Б those are too thin to protect you from a shock and are often not made entirely of rubber)б Another technique is to hang beneath a helicopter. Since neither the worker nor the helicopter is connected to the ground (like a bird), the worker just has to make sure he only touches one wire at a time. Despite continual safety improvements, being a power linesman is still one of the ten most dangerous jobs in America. So, itБs a good idea to stay away from electrical wires unless youБre a trained professional Б or a bird. б Thanks to Naveen Surisetty from Visakhapatnam, India, for this question. б Dated: December 10, 2013 Imagine if your eyes could see moving. You could then see the stream of fast-moving electrons on these, which have the power to give you the shock of your life, literally! How do then, not get?
Do they have some? Are they immune to current, that no matter what they don t get electrocuted? Or is it something they hide under their feathers, a secret weapon to counter electricity, and then one day deny us the power of the and take over as the new rulers of the world? Well jokes aside, the most simple explanation is that both the bird s legs are on the same wire, and are at the same potential, hence eliminating the case of current/moving electrons. Electrons basically move from regions of high potential to low potential, so if the bird had one leg on the wire and the other on the electric pole or the ground, then its legs would be at different potential, electrons would move and the bird would be electrocuted. One can also question, Doesn t the squirrel form a closed circuit for the current to move?. Well that is true, but the concept of current is that it moves along the. Between a piece of wire and the bird on the wire, the path of least resistance is the wire, again explaining why the bird does not get electrocuted. Well we are happy for the birds that they have a place to rest without a worry, but there are still lots of cases of electrocution. A video showing a bear electrocutedP A man from is struck by 50000 currentP We wait for the day when we can transmit power wirelessly, maybe we can then avoid accidents while at the same time also save money on the use of these wires. (sciencedaily. com)
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