Writer Questions

Discussion in 'General Electronics Chat' started by Squid, Jun 24, 2005.

  1. Squid

    Thread Starter New Member

    Jun 24, 2005
    2
    0
    Hello. I'm writer and have electricity questions about two possible scenarios. In scenario one, if I'm touching an electric fence and being shocked, and then someone else touches me, do they get shocked too? In scenario two, if I'm touching someone else and then I touch the electric fense, do we both get shocked, just me, or just the other person. In both scenarios, me and the other person are touching the ground at all times. I'd appreciate any help.
     
  2. thingmaker3

    Retired Moderator

    May 16, 2005
    5,072
    6
    Both will get shocked.

    We are taught repeatedly that we must never ever directly touch a co-worker who is being electrocuted, lest we share their fate. We are to use a (wooden) 2x4 or broomstick to knock them away from the connection, or throw a rope or strap around them and pull. (The working theory is that breaking their ribs is better than letting them die.)

    IIRC, a cousin of mine found out that the cow fence bit harder when he was barefoot than when he had his sneakers on.
     
  3. n9xv

    Senior Member

    Jan 18, 2005
    329
    1
    - - - ELECTRICUTION - - -

    Its the gift that keeps on giving, as long as your touching the other person!
     
  4. Smack

    New Member

    Jun 25, 2005
    6
    0
    Why is it when 5 people touch each other and one of them then touches the fence, the one farthest feels a bigger shock.

    I alway wondered
     
  5. kensplace

    New Member

    Jun 25, 2005
    7
    0
    If your going to touch an electric fence, stand on a thick polystyrene block so you are insulated from the ground, that way you wont get a shock. But if another person touches you, then they will get a shock....
     
  6. Squid

    Thread Starter New Member

    Jun 24, 2005
    2
    0
    Thanks to all. I had asked family about this. One is an oilfied electrician. The other is a retired science teacher. The electrician said both would get shocked. The teacher said just the second person. After reading about voltage on this website, I thought both would be shocked but wasn't sure. The comments here have cleared it up for me. Thanks for your help. Smack does raise an interesting question, though. This electric fence phenomena did add to my confusion and the science teacher's.
     
  7. Erin G.

    Senior Member

    Mar 3, 2005
    167
    1
    Coming from a power plant & manufacturing electrician,...

    When someone gets a serious shock, the burn damage to the skin is usually worse at the point where the current leaves the body. It would stand to reason that perhaps more current is leaving the last person in the chain than the four in front of him.
     
  8. Firestorm

    Senior Member

    Jan 24, 2005
    353
    0
    well coming from a farm and havin 2 build fences my best advice is dont touch um lol ;). If you touch the other theyll get shocked but in some instances you can touch it and not get shocked. Since the voltage is to high it has very low amperage. This is y you hear a pop when you touch the ground wire and hot wire together about every sec or so. thx l8er

    -fire
     
  9. Erin G.

    Senior Member

    Mar 3, 2005
    167
    1

    That's great advice!! :)
     
  10. Garry

    Member

    Jul 1, 2005
    12
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    British TV show "Brainiac" had a nice gig about this on ... they tested different scenarios ... basic result is as to be expected:

    - when 1..n people who are not grounded (i.e. standing on a plastic bag etc.) in line are connected to an e-fence, nobody gets a shock.
    - when 1..n people who are all grounded in line are connected to an e-fence, the shock reduces over the distance
    - when 2..n people of which the first n-1 are not grounded and the last one is are connected to an e-fence, all receive the same strength shock ...

    I could try to rip the part from the show if anybody is interested ...
     
  11. buddyengineers

    Member

    Mar 19, 2005
    26
    0
    Erin seems to have given a nice xplanation to why the last person gets the max shock, but then Garry u have said in ur second point abt shock reducing with distance,
    Cant this case be taken as parallel resistance(1st person touchin the fence and gnd, others touching the person ahead of him and also gnded) so the current tht crosses should be almost equal through all and everyone should get an equal shock. So the shock shd be neither more nor less for the last person.
    I hope i have got myself right in this case, let me know if i am wrong somewhere.
    A Simple topic but nice discussion. Keep posting on this topic.
    Cya
    Dilu
    P.S. Garry let us know if u can upload tht "brainiac" rip on any website.., plz pass on the link to us.
     
  12. Erin G.

    Senior Member

    Mar 3, 2005
    167
    1
    Buddy,

    I don't personally know anyone that has tried to line up three or four people, have one grab an electric fence, and then take a survey to see who got hurt worse: So really this is a mental exercise. (With the exception of the "Brainiac" experiment, which I haven't seen.)

    So let's take this from the top,...

    A human body is essentially a resistor, so assume for our purposes that all of the bodies have EXACTLY the same resistance, and that each body also has the EXACT same resistance to ground.

    The first rule of a series circuit is that the total current in the circuit is equal to the current in any other part of the circuit. Bodies(resistors) in series would drop the voltage as it passed through each body(resistor), but the current would remain the same. So the voltage should diminish over the distance. The current, however, should remain constant. The person in line who is not insulated will find out that hertz hurts.

    If everyone is standing in their bare feet, then we have a parallel circuit to ground. In a parallel circuit, if the branches all have the same resistance, then each will draw the same amount of current. Assuming a PERFECT parallel circuit (all resistances of individual bodies, and body to ground resistances exactly equal) each body would conduct the same amount of current to the ground, no matter where they are in the "circuit". So they all should receive an equal shock.

    Thinking about this, (outside of our experimental vacuum above where everything is perfectly equal) in the real world I would think that the person with the combination of the least amount of bodily resistance and the least amount of resistance to ground, will probably get the most amount of shock no matter where they are in line.

    I, for one, will not volunteer to field test my theory, hehe ;)
     
  13. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
    Hi,

    There is an interesting self-control scenario involving electric fences. Imagine a fence with two rows of barbed wire, and a charged electric line on top. To cross it, your buddy holds the charged line up with a stick. You have just stepped over the barbed wire, and are ducking under the charged wire when the stick breaks.

    Imagine straddling barbed wire as a hot wire bounces off your back and not needing stiches afterward.
     
  14. Firestorm

    Senior Member

    Jan 24, 2005
    353
    0
    Well that would suck beenthere. My dad had a couple of workers who weren't xactly wut u would consider smart. They were sent to rebuild a fence and make sure the post were striaght. When dad came back they were crooked and didn't hardly look like a fence. So, Dad made um pull up the posts and reset them. When that was done, that afternoon dad turned on the fence charger and all of the sudden one of the workers screamed like hell. Turns out he was so mad at the fence he decided to piss on it. Never showed up to work after that day lol.

    I have tryed several people holding hands to touch it and supposedly the one at the end gets all the shock but we can only try once for obvious reasons :lol:
    thx l8er

    -fire
     
  15. thingmaker3

    Retired Moderator

    May 16, 2005
    5,072
    6
    [attachmentid=777] :D
     
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