Why do birds do not get shock when they sit on high current carrying wires & houmans don't?
373398
The high current wires carry only one of the two poles (positive and negative) of current. The other pole travels through the earth. Therefore, birds and also humans will not get a shock as long as they touch only one wire. Birds are very small and there is little risk that they touch anything else. Humans, at the contrary, easily can touch the wire and the metal mast carrying the wires, in which case the second pole of the current, travelling through the ground, reaches the body together with the one travelling through the wire and originates the shock.
563909
Canaries need more oxygen in the air than we do.\nMiners used to take canaries into the mine shafts and if it died in a particular shaft, the miners avoided it because there would be less oxygen as they went furhter into the shaft.
1077289
The red balls collect static electricity in the air and eliminates even the slight possibilities of shorthing two separate wires that could cause a massive blackout in the region.\nThe gray balls emit high frequency sounds that are very disturbing to the birds so that the birds do not sit on the wires and short them.\nBoth colors have transmitters that alert the pilots that fly by also.
1026855
I agree with the others, you questions is unclear.\n\nThe only thing I can say (wild guess) is that there are some telemetry circuits that use a slight current as a zero point.  If the current actually goes to zero, they know there is a problem with the circuit.  Otherwise, they might not know until a lot of damage has been done, depending on what is being monitored.
548516
For a human to walk on a power line and live, you'd need to scale up the powercords to make the human represent the size of a pidgeon.\n\nThe reason being, if you're standing on a wire, your head may be closer to a wire.  For example...\n\n---------  +\n\n---'-----  -        <-bird\n\n\n---------  +        (+ is positive, - is negative)\n    o\n    |\n---------  -        <-human\n\nThe human body is about 80% water.  As as we all know, water conducts electricity.  As such, your body has a lower "resistance" then the air surrounding it.  So it may be safe to say (approximatly)\n\nHuman's resistance (between lines): 1.1 million ohms.\nBird's resistance (between lines): 20 million ohms.\n\nIf the voltage is sufficient to pass through the 1.1 million ohms, you'll be fried.  The amperage will instantly kill you.\n\n---------------------------------------\n\nIf you're talking about just walking on an electrified line (with no others around), then yes, you should be able to walk along it.  The current isn't different in the same line, so the electricity won't travel through your body.
333005
TO GET SHOCK THERE SHOULD EXIST A SHORT CONTACT THAT MEANS IF BIRD TOUCHES ONLY PHASE WIRE OR NEUTRAL WIRE IT DOESNT GET SHOCH BUT IF IT ACCIDENTALLY TOUCHES BOTH THEN IT WILL DIE
884352
Interesting question. See, in order to achieve lift, an airfoil (or bird's wing in this case) must deflect air down in order to achieve an upwards lift. This is a consequence of Newton's 3rd Law ("For every action, there is an equal and opposite reaction").\n\nNote that this DOES NOT imply that the downwardly-deflected air reacts against the truck bed. This is a common misconception; note that rockets have no trouble zipping around space, even though their exhaust has nothing to react against. \n\nOne caveat though: naturally, if the airfoil or wing passes close enough to the truck bed, the deflected air will push against it, causing a small force, like when you feel the breeze coming off of a ceiling fan. However this is simply a consequence of the proximity of the objects rather than a physical interaction between them.\n\nSo in answer to your question, yes. If every canary were to take flight at the exact same instant, and the truck is tall enough that the air deflected from their wings does not reach the floor, then the truck will measure its "canary-free" weight on the scale:\n\nW = (M - m)*g\n\nW = 19,900 lbs\n\n-----\nBONUS POINT\n-----\n\nFish are different from birds in that, for a bird to move in 3-dimensions, it has to deflect air (as discussed above). A fish, however, does not. The fish maintains its position using Archimedes Principal; that is, by absorbing and expelling water or expanding and contracting its rib cage, it can alter its "altitude" in the water, just like a submarine.\n\nThe bird remains in the air by constantly deflecting it down; a fish remains above the bottom of the tank by actually resting on the water. In this sense, the weight of the fish is transferred through te fluid as though the fish were part of the tank itself (regardless of the fish's position therein).\n\nThus: canaries flying inside the truck - the truck measures it's empty weight; fish swimming inside the truck, the truck will measure its loaded weight.\n\n\nHope that helps! :)
1150283
The internal circuits of most stun-guns are fairly simple, either based on an oscillator, resonant circuit and step-up transformer or diode-capacitor voltage multipliers to achieve the continuous, direct or alternating high-voltage discharge may be powered by one or more 9 V battery depending on manufacturer, and model.  The recipient of the tazer shock (poor fellow) is actually imobilized as two metal probes touch the skin and send a high-voltage current through his or her body, causing great pain and temporary paralysis.
700029
Ideally for the bird it must contain enough energy to justify the energy consumed in gathering it.  If not then the bird was better off staying put.
263815
The electric eel (Electrophorus electricus) does not produce a _small_ electric shock, but a strong and dangerous one.\nHowever, there are several species of freshwater fish that are related to electric eels (they belong to the same order Gymnotiformes) that produce weaker electric pulses; these are the knifefishes (genera Gymnotus, Ramphichthys, Eigenmannia). \n\nIn addition, there are several fishes that can produce electric fields and eventually shocks: all true rays (genus Raja and others), torpedo rays (genera Torpedo, Discopyge, etc), the electric catfish (Malapterurus electricus), electric stargazers (genus Astroscopus), the elephantnoses (Mormyridae), etc.
562822
You know how the bird works, right? Evaporation of water on the felty beak cools an alcohol solution which then changes the balance point or the bird?\n\nEssentially, what is going on is movement of fluid that heats and expands and then cools and contracts. Sound familiar? The amount of heating and contraction is minimal in the finely balanced bird and the temperature difference doesn't have to be large. Now, the more energy you extract from the system, the greater the difference in temperature will have to be (to move more fluid to overcome more resistance to motion). Well, the idea is already in use, although the set up isn't the same as the bird, the principle is the same.\n\nWherever you have naturally occuring heat close to naturally  occuring cold, you can take advantage of the difference to generate energy. Solar heat engines rely on this by concentrating the heat energy from the sun to create the hot side. Geothermal engines rely on this by taking advantage of the cooler conditions underground.\n\nThe real problem is getting enough bang for your buck. Running a pump this way to move water far from electrical supplies is a good use, but for most other uses, it's just cheaper and more reliable to use some sort of fuel.
143714
because they are not grounded, in fact, u can sometimes see utility workers high up on the tension wires with thousands of volts going right over them
600837
Electric eels are not true eels, they are only eel-like in shape. Electrophorus electricus is famous for its ability to produce strong \nelectrical currents, reaching 500-650 volts. This strong discharge is used to stun or kill prey. This electrical discharge is also used to ward off potential predators.\n\nUp to 6,000 electroplates are arranged like a dry cell in the eel's body. Its internal organs are all in a small area behind the head, with 7/8 of the eel being tail. The electrical shocks come from muscles mainly in the tail portion of the electric eel's body. The body of an electric eel is similar to a battery. The tail end of the eel has a positive charge and the head region is negatively charged. When the eel touches its tail and head to other animals it sends electric shocks through their bodies. When the eel is at rest, there is no generation of electrical impulses.
1056009
Well, this story is probably apocryphal. But the MythBusters did a program on this and determined that even wet twine is a pretty poor conductor. Add to that the probability that the kite was tied to a stake in the ground and the actual shock potential would be pretty minimal.\nAccording to the story, Franklin did touch a key with his knuckle and noticed a spark, so he might have done his experimenting before the kite was actually struck, but after it had time to accumulate a fair static charge.\nAnyway, good question, there. And remember what they always warn you on TV "Don't try this at home, Kids!"
63919
Because of the way their legs are built.\nThe tendons in bird's legs are arranged as a pulley-rope system so that the weight of the animal pulls on these tendons and keeps their fingers closed at rest. Thus they do not require voluntary muscle action to maintain their grasp on branches.\nThis is specially characteristic of songbirds. Others may rely on nests, platforms or other types of dwellings
436333
First find something fibrous like a carpet, a fuzzy carseat, or something else like that.  Rub your clothing on it for a good bit.  Make sure you aren't standing on or around something metal or it'll ground you instantly (thus negating any charge you'd build up).\n\nAdditionally, a factor that you have little control over--you must be in an area that has relatively low ambient humidity (<<10%).  If you live in a Rainforest, for example, pretty much nothing you do will generate enough static to create a shock.  Good luck and happy shocking.
557631
Current kills, not voltage.\n\nThe number of volts in an electrical is not so much as important as the current (amps) which are carried through the body.  If you have ever been shocked by static electricity or a Van de Graaf generator, you have experiences (and lived through) shocks of very high electrical potentials (very high volages), but the current was just too low to really effect you.\n\nIt does not take much current to stop a heart, just a few tenths of an amp (not a lot at all) can kill you if it runs through your body the right [or in this case, wrong] way,\nhttp://www.physics.udel.edu/wwwusers/watson/scen103/colloq2000/safety.html\nhttp://www.physics.ohio-state.edu/~p616/safety/fatal_current.html\n\nBut to get back to your question,\nit is entirely possible to be killed by sticking a screw driver into an electrical socket...this probably wouldnt be a good thing to test out though.  If you are grounded when you stick the crew driver in, the current could travel through the screen driver, into your arm, perhaps through your chest and heart, and down your leg.