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    So, I have been looking around trying to find out why birds don't get electrocuted when they perch on "naked" power lines. Some say it is because their legs are covered with a layer of insulating material and as such the current doesn't flow through them, while some say the current actually flows through them, but they are unhurt because the system is not "earthed". Since the two points cannot both be true (I think ), which do you think correctly explains the phenomenon. Or any other explanation?
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    I was told that birds don't get electrocuted (when they're perching on the pylons) because they don't touch the ground... so the 'circuit' is incomplete? :confused:

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    Yea, I heard that too. But I have actually seen birds get killed up there even when they didn't touch the ground. That's why I had to dig further....
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    (Original post by ClosetGenius)
    But I have actually seen birds get killed up there even when they didn't touch the ground.
    Then those birds must have touched the cable and the pylon at the same time so the pylon provided a route to earth.
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    If the bird is touching nothing else but the wire, the end destination for the current is the same. It's much easier for it to go through the wire as it's more conductive so the bird doesn't really get any current going through it.
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    (Original post by karmacrunch)
    I was told that birds don't get electrocuted (when they're perching on the pylons) because they don't touch the ground... so the 'circuit' is incomplete? :confused:

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    Correct. Have a gold star.

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    (Original post by dontbtz)
    ****ing hell guys....
    What, sorry?? :erm:
    (Original post by ChaoticButterfly)
    Correct. Have a gold star.

    Yay! :ahee:




    A gold star... really? :rolleyes:

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    (Original post by karmacrunch)
    What, sorry?? :erm:


    Yay! :ahee:




    A gold star... really? :rolleyes:

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    You too old now for gold stars?
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    (Original post by ChaoticButterfly)
    You too old now for gold stars?
    Maybe... :colone:

    Not really, no. I actually got one today but it was purple... :rofl:
    (Original post by dontbtz)
    Haha, sorry. That was probably a bit rude of me. I was just kinda surprised that you guys didn't know. :rolleyes: I guess you don't study physics? :P
    I'm 14 so no... I was actually told this by a teacher. ^^ How isn't it right, Butterfly's just said it was? He studied Physics. I'm not sure to be honest. XD

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    For the birds to be electrocuted they would have to conduct the electricity through their body. This does not happen.

    The reason is that electricity always follows the path to ground with the lowest resistance. Now a bird could form part of an electrical circuit in this situation, but in reality a bird is a worse conductor than an electrical cable, so the current is not going to short-cut across the bird's feet.

    Likewise, if you were to hang from a cable by your hands, you'd be fine. It's easier for the current to just keep going through the wire. But if your feet touched the ground (or anything which could conduct to the ground) it would form a circuit which could bypass all the resistance involved with flowing miles and miles overland. Bad things then happen.
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    (Original post by karmacrunch)


    I'm 14 so no... I was actually told this by a teacher. ^^ How isn't it right, Butterfly's just said it was? He studied Physics. I'm not sure to be honest. XD

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    Just because I studied physics at uni doesn't mean I am knower of everything :lol:

    As far as I am aware you are more or less correct. Current follows the path of least resistance. When the bird is just sitting on the wire the electricity would have to go though the bird then though the air to the ground. The resistance for that to happen is massive so the lazy electrons just knock along the wire instead. If a fisherman were to hit a cable with his fishing rod there is a good chance he would get electrocuted as the current may travel though the rod and then though him to the ground as the resistance is much less than that of the bird situation above.

    That's my reasoning. Anyone can correct me if they know better. Electricity was never my strong point

    Science has experts, not priests. Nothing they say is gospel.
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    (Original post by ChaoticButterfly)
    Just because I studied physics at uni doesn't mean I am knower of everything :lol:

    As far as I am aware you are more or less correct. Current follows the path of least resistance. When the bird is just sitting on the wire the electricity would have to go though the bird then though the air to the ground. The resistance for that to happen is massive so the lazy electrons just knock along the wire instead. If a fisherman were to hit a cable with his fishing rod there is a good chance he would get electrocuted as the current may travel though the rod and then though him to the ground as the resistance is much less than that of the bird situation above.

    That's my reasoning. Anyone can correct me if they know better. Electricity was never my strong point

    Science has experts, not priests. Nothing they say is gospel.
    As much as I disagree with your cat fetish, your explanation is pretty accurate.

    The potential difference between a wire and ground will always be greater than that between the wire and the next bit of wire. The greater the potential difference between where the electrons are and their potential destination, the more attracted they are to that destination.

    A living body might be less conductive than wire but if the destination on the other end is more attractive than continuing to travel along the wire, it's worth it.
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    (Original post by HandmadeTurnip)
    As much as I disagree with your cat fetish, your explanation is pretty accurate.

    The potential difference between a wire and ground will always be greater than that between the wire and the next bit of wire. The greater the potential difference between where the electrons are and their potential destination, the more attracted they are to that destination.

    A living body might be less conductive than wire but if the destination on the other end is more attractive than continuing to travel along the wire, it's worth it.
    Good to know I learnt something in the last 5 years lol
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    Both of the birds feet are touching the same conductor, which are for all intents and purposes at the same potential difference. No potential difference, no current. No current, no shock.

    It's the same principle as to why all the metal pipes, sinks etc in your house are cross bonded (ultimately joined together at the distribution unit): in the event of an electrical fault where, for example, a pipe might become live, all conductive parts of the house become live to the same voltage and thus have no potential difference between them. This means you won't get shocked by touching a 'live' pipe and an earthed pipe.

    You could hang off the power line yourself (as long as the voltage was not sufficient to 'jump' from your feet to the ground or to another phase) and you'd be fine. Honest!
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    Thanks y'all. So, the insulating feet thing is incorrect then.

    I don't think hanging from a power line to proof that point will be necessary though
 
 
 
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