paper clip in a power outlet

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paper clip in a power outlet

Postby TizzyFoe » Tue Dec 04, 2007 6:38 pm UTC

i've gotten into a debate with some friends of mine, about what will happen if i stick a paper clip into a power outlet. I think the electricity will flow through the paper clip which will make it very hot and blow out a fuse or circuit breaker, but i dont think i will get shocked (maybe just burned).

ALL of my friends are SURE that i will be shocked. They either think that simply touching something with a charge will shock me, or that my feet will "ground" me causing me to be shocked.

We debated this for quite a while, i talked about how birds can sit on power lines and be fine, they talked about electric fences. After debating it i was even more confident i wouldn't be shocked but still couldn't convince them. I'm afraid to try it because of things like starting a fire ext.

I know there are lots of smart sciency people here. What do you guys think will happen, and why?

Magistrate warning: while it is interesting to discuss extremely dangerous experiments, they are, well, extremely dangerous. Please do NOT try this at home, or in any other situation where you do not already know beforehand exactly what's going to happen.
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Re: paper clip in a power outlet

Postby btilly » Tue Dec 04, 2007 7:59 pm UTC

TizzyFoe wrote:i've gotten into a debate with some friends of mine, about what will happen if i stick a paper clip into a power outlet. I think the electricity will flow through the paper clip which will make it very hot and blow out a fuse or circuit breaker, but i dont think i will get shocked (maybe just burned).

That is what I think as well.
TizzyFoe wrote:ALL of my friends are SURE that i will be shocked. They either think that simply touching something with a charge will shock me, or that my feet will "ground" me causing me to be shocked.

I guess they didn't play around with a wire coat hanger and an electric socket like I did when I was 10. :roll:

Electric wires are not perfectly grounded, but on average they are reasonably close to it. Plus once you blow the fuse, the wire no longer is carrying a significant charge. And the resistance of the human body is quite high.
TizzyFoe wrote:We debated this for quite a while, i talked about how birds can sit on power lines and be fine, they talked about electric fences. After debating it i was even more confident i wouldn't be shocked but still couldn't convince them. I'm afraid to try it because of things like starting a fire ext.

Birds can sit on power lines and be fine because the bird isn't grounded. It is fine to have a high charge. It stops being fine when it has an opportunity to discharge through you. This is why for some work with very high power lines it is actually easier to have someone hanging out of a helicopter doing the work than to have someone supported from the ground!
TizzyFoe wrote:I know there are lots of smart sciency people here. What do you guys think will happen, and why?

I think there will be a large spark when the current jumps through the paper clip. This will generate a bang and a sudden large current. If you have good wiring, a fuse will then blow and someone will have to go flip the breaker. If you don't have good wiring, you might start a fire. I don't know how hot the paper clip will get. A coat hanger wouldn't even get warm, but a paper clip should get warmer than a coat hanger.

I think this based on both a basic knowledge of how electricity works and an experiment.

Incidentally wouldn't recommend doing this. Or if you must, have a really good excuse. (In hindsight, "I'm just a kid!" wasn't really a good enough excuse.)
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Re: paper clip in a power outlet

Postby scowdich » Tue Dec 04, 2007 8:00 pm UTC

Prepare to get knocked flat on your ass, partly from the current traveling through you (you will be grounded), partly from the paperclip forcibly removing itself from the outlet. Don't say we didn't warn you.

EDIT: Also, birds are fine on telephone wires because they don't form any path to ground. You, by standing in a place, do.

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Re: paper clip in a power outlet

Postby Nullcline » Tue Dec 04, 2007 8:10 pm UTC

The outlet will spark before you make contact. The paper clip itself will act as a ground for the air between the contact and the clip. But if you do brave through the fireworks and make contact, it will take almost a second before you notice the muscles in your lower arm tightening and(probably) breaking the circuit. In case you're wondering(and you should be)I've done this with both a bare copper wire and a screwdriver. The wire sparked like heck(a lot more than the paperclip will) and I'm pretty sure I didn't make contact. The screwdriver did nothing until I grabbed the faucet with my other hand(I was in my bathroom.) Then I felt all of the muscles in both of my arms tighten immediately and I made a sound similar to what I imagine a giant ground sloth would sound like mid-coitus. Your experience will be something in between. If you do not do this you will regret it for the rest of your life.

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Re: paper clip in a power outlet

Postby btilly » Tue Dec 04, 2007 9:10 pm UTC

Nullcline wrote:The outlet will spark before you make contact. The paper clip itself will act as a ground for the air between the contact and the clip. But if you do brave through the fireworks and make contact, it will take almost a second before you notice the muscles in your lower arm tightening and(probably) breaking the circuit. In case you're wondering(and you should be)I've done this with both a bare copper wire and a screwdriver. The wire sparked like heck(a lot more than the paperclip will) and I'm pretty sure I didn't make contact. The screwdriver did nothing until I grabbed the faucet with my other hand(I was in my bathroom.) Then I felt all of the muscles in both of my arms tighten immediately and I made a sound similar to what I imagine a giant ground sloth would sound like mid-coitus. Your experience will be something in between. If you do not do this you will regret it for the rest of your life.

The significant difference between this experience and mine is that I was on a reasonably well-insulated surface (a wood floor) and I stuck both ends of the coat hanger into both ends of the socket. So no current went through me.

By contrast it seems that you stuck one end into the socket and then were grounded. Resulting in current running through you.
Nullcline wrote:I was retarded when I was 14.

Who wasn't? :D
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Re: paper clip in a power outlet

Postby TizzyFoe » Tue Dec 04, 2007 9:24 pm UTC

i have stuck one end of a paper clip in the outlet (nothing at all happened). I should have specified, i was talking about sticking each end of the paper clip into the 2 different sockets (thus connecting them).

scowdich wrote:Prepare to get knocked flat on your ass, partly from the current traveling through you (you will be grounded), partly from the paperclip forcibly removing itself from the outlet. Don't say we didn't warn you.


why do you think the current will travel though me and not from one end of the outlet to the other? What force will push the paper clip out of the socket?
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Re: paper clip in a power outlet

Postby btilly » Tue Dec 04, 2007 9:41 pm UTC

TizzyFoe wrote:i have stuck one end of a paper clip in the outlet (nothing at all happened). I should have specified, i was talking about sticking each end of the paper clip into the 2 different sockets (thus connecting them).

scowdich wrote:Prepare to get knocked flat on your ass, partly from the current traveling through you (you will be grounded), partly from the paperclip forcibly removing itself from the outlet. Don't say we didn't warn you.


why do you think the current will travel though me and not from one end of the outlet to the other? What force will push the paper clip out of the socket?

If you're well-grounded then current can travel through you to ground. This causes involuntary muscle spasms. If you're well grounded and don't insert the paper clip perfectly, this circuit will be completed before the one from one end of the paper clip to the other.

If you're well insulated from the ground, this is a non-issue.

Random historical trivia. When Benjamin Franklin did his famous kite-flying experiment he took precautions to make sure the kite was grounded and his hand was insulated from the kite. He took no damage. Some imitators tried the same experiment without those precautions and suffered tragic results.
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Re: paper clip in a power outlet

Postby MalaysianShrew » Wed Dec 05, 2007 12:54 am UTC

Yeah, you will get shocked. Once I was trying to plug something in behind a desk so I was just trying to find the outlet by feel. Well, when I plugged it in, I had one finger on one of the prongs. A shock went up my arm as I plugged it in which didn't feel too nice.

I suppose a safer and similar experiment would be to make a small circuit with a battery or two and some copper wire and complete the circuit with a paperclip in your hand.

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Re: paper clip in a power outlet

Postby arkady » Wed Dec 05, 2007 1:08 am UTC

This comic comes to mind.


The current flowing across the paper clip will depend on the resistance of the paper clip (V=IR, V=240 Volts).
Assuming the experimenter is also a conductor, and is grounded, a potential divider will be created:

Code: Select all

+240V -|
       |
       | R (PC Left)
       |
       |----------- Experimenter, R (E)
       |
       | R (PC Right)
       |
   0V -|


Let the paper clip have a resistance of RPC Left+RPC Right=RPC Total, and the experimenter have a resistance of RE.

According the the equation for the voltage going across the experimenter is [1]:

VE = Vin(RPC Left * RE) / ((RPC Left * RPC Right) + (RPC Left*RE) + (RPC Right * RE))

Vin = Input voltage (in the diagram, 240V, which is standard for the UK.)

If RE > 2RPC Total this gives almost exactly a straight line fit to the tune of VE=240V-L/240 (L = distance from live plug / length of the paper clip)

The voltage running through the experimenter will be the full Vin if they are touching the paper clip at the live end, will therefore be the full 240V, but will drop off linearly to 0V at the other end. The approximation is valid because the resistance of the paper clip (approx. 5cm long, resistance is 0.36 mOhms ) is much less than the resistance of a human (40-150 kOhms (dry)[3]).

Using these numbers, and the table given on [3], and assuming that the current supplied is 240V AC at 60Hz, we can predict:
A slight sensation felt at hands for 1 > L > 0.94
Will be perceivable at 0.94 > L > 0.82
Painful, but controllable at 0.82 > L > 0

These are for CLEAN, DRY SKIN!

These don't take into account affects involving the paper clip being thrown from the socket.

Be careful - I suggest you replace yourself with a resistor of about 40 kOhms (4 kOhms for wet skin, 100 Ohms for the case where you're standing in a bucket of water) and use plastic pliers to control the experiment, along with a Ammeter so you can see how much current would be flowing through you.


[1] http://en.wikipedia.org/wiki/Potentiome ... _operation 5th December 2007, 00:49 GMT
[2] http://www.aircraftmaterialsuk.com/data ... lstst.html 5th December 2007 00:50 GMT
[3] http://www.allaboutcircuits.com/vol_1/chpt_3/4.html 5th December 2007 00:53 GMT
Last edited by arkady on Wed Dec 05, 2007 4:56 pm UTC, edited 1 time in total.
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Re: paper clip in a power outlet

Postby Marvin » Wed Dec 05, 2007 2:21 am UTC

hmmm... let's see... suppose you have good shoes that insulate well, you put paper clip into socket, in less then a moment a fuse goes boom and nothing happens

if you have bad fuse, the paper clip gets hotter and eventually melts...

now if you don't have good shoes, it depends whether you put the paper clip first in 0V or 240V, if you put it first in 0V then you should have no problem as long as you let it go as soon as you do it, the clip will get hot very fast, and as it gets hotter it's resistance grows, and the more resistance the clip has, more current goes into your hand.
If you put it first in 240V you should have an standard electric shock... not nice, but survivable... mostly...

now i predict a good fuse, and good shoes, and nothing should happen...

oh... and one more VERY important thing... you want to do thin with ONE hand... and ONE hand only...

(or maybe, better to say... you don't really want to do this... and if you do, try an insulated wire first just to check if your fuses are good... and change the fuse before you attempt of sacrifice for science :mrgreen:)
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Re: paper clip in a power outlet

Postby hipp5 » Wed Dec 05, 2007 2:43 am UTC

When sticking it into only one hole of an outlet, hole choice matters. One hole is the supply 'live' wire while the other is a return 'dead' wire. If it has a third hole that hole is the ground.

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Re: paper clip in a power outlet

Postby thoughtfully » Wed Dec 05, 2007 4:21 am UTC

TizzyFoe wrote:We debated this for quite a while, i talked about how birds can sit on power lines and be fine,


btilly wrote:Birds can sit on power lines and be fine because the bird isn't grounded.


scowdich wrote:EDIT: Also, birds are fine on telephone wires because they don't form any path to ground.


Honestly, people. I'm sure you are all products of fine university educations, but you and all those looney profs really should know better.

The birds wouldn't get shocked even if they were grounded. Power lines are insulated!

EDIT: You teach voodoo freaky nogoodnesses when reality takes a back seat to pedagogy.
EDIT: Simplification is okay. The Bohr Model is good enough for kids, for instance. I say this is qualitatively distinct.
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Re: paper clip in a power outlet

Postby trickster721 » Wed Dec 05, 2007 4:40 am UTC

The danger isn't really that the electricity will travel through your entire body and into the floor. It doesn't need to. Using an inch of your finger to create a parallel circut is unpleasant enough.

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Re: paper clip in a power outlet

Postby oxoiron » Wed Dec 05, 2007 5:30 am UTC

1) Open the circuit breaker/remove fuse.
2) Insert the paper clip, completing the circuit.
3) Close the circuit breaker/replace fuse.
4) Examine paper clip and remove from socket if necessary and possible.
5) Reset breaker/replace burned out fuse.

Alternatively, burn down your house with unprotected circuits. :)
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Re: paper clip in a power outlet

Postby hobbesmaster » Wed Dec 05, 2007 5:44 am UTC

thoughtfully wrote:Honestly, people. I'm sure you are all products of fine university educations, but you and all those looney profs really should know better.

The birds wouldn't get shocked even if they were grounded. Power lines are insulated!


Power lines are not insulated. Birds are not electrocuted because they contact two points on the line at the same potential. If they bridged two lines, or for some funky reason (crazy transient) the two points on the line the birds were connecting were at a different potential, then they would be electrocuted.

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Re: paper clip in a power outlet

Postby btilly » Wed Dec 05, 2007 6:01 am UTC

thoughtfully wrote:
btilly wrote:Birds can sit on power lines and be fine because the bird isn't grounded.

Honestly, people. I'm sure you are all products of fine university educations, but you and all those looney profs really should know better.

The birds wouldn't get shocked even if they were grounded. Power lines are insulated!

EDIT: You teach voodoo freaky nogoodnesses when reality takes a back seat to pedagogy.
EDIT: Simplification is okay. The Bohr Model is good enough for kids, for instance. I say this is qualitatively distinct.

I'm curious whether you'll apologize after you realize that you are mistaken on the facts. Power lines are generally not insulated for the simple reason that insulation costs money and they get excellent insulation for free just from being in the air.

If you doubt me, google for "power lines insulated" and read a few links. Then decide whether you feel like apologizing for your previous state of ignorance.
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Re: paper clip in a power outlet

Postby BNOOOOGERS » Wed Dec 05, 2007 8:39 am UTC

My experience in the matter comes from attempting to measure the current in an outlet in my kitchen. I used a standard ammeter, but I neglected to switch it from DC to AC. As soon as I stuck the second prong in the outlet, sparks flew everywhere, molten droplets of metal burned holes in my calendar (it was located on the counter right below the outlet) and the outlet was fried. A paper clip will not take long at all to heat up, and unless you want some pretty nifty burns and a funny story of how foolish you were as a young 'un, I would not recommend your experiment.

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Re: paper clip in a power outlet

Postby TizzyFoe » Wed Dec 05, 2007 8:44 am UTC

arkady wrote:The approximation is valid because the resistance of the paper clip (approx. 5cm long, resistance is 0.36 mOhms ) is much greater than the resistance of a human (40-150 kOhms (dry)[3]).



isn't this the other way around? Surely the resistance of a metal paper clip is lower then the resistance of the average human body.

hipp5 wrote:When sticking it into only one hole of an outlet, hole choice matters. One hole is the supply 'live' wire while the other is a return 'dead' wire. If it has a third hole that hole is the ground.


is this true? There so much about electricity i don't know. In AC doesn't the live wire alternate?

The hole deal with grounding doesn't make a lot of sense to me either. What causes electricity to flow into the ground and not simply back out the other wire?

BNOOOOGERS wrote:A paper clip will not take long at all to heat up, and unless you want some pretty nifty burns and a funny story of how foolish you were as a young 'un, I would not recommend your experiment.


Pff, i'm not concerned about a minor burn on my fingers, there technically a $60 bet on the line if i actually go threw with it. I'm not at all a young 'un, but i guess that would make the story all the more foolish :oops:
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Re: paper clip in a power outlet

Postby evilbeanfiend » Wed Dec 05, 2007 9:58 am UTC

yes the live wire will have an alternating potential on it, the neutral and ground have 0 potential (in an ideal system, in real circuits there can be a pd between different grounds), ground is essentially a 'back up' neutral so the live wire doesnt try to ground through casing etc, if the neutral wire is cut. current doesn't just take the path of least resistance, it take all paths in inverse proportion to to the resistance on each path (assuming a potential difference) i.e. if you are in parallel with a resistor with 1/2 the resistance of you, it will take 2/3rds of the current and you will take 1/3rd.

last time i checked 0.36 mOhms < 40-150 kOhms. which is exactly what you would expect given that paper clips are usually made from metals that have pretty good conductivity
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Re: paper clip in a power outlet

Postby Marvin » Wed Dec 05, 2007 10:19 am UTC

evilbeanfiend wrote:last time i checked 0.36 mOhms < 40-150 kOhms. which is exactly what you would expect given that paper clips are usually made from metals that have pretty good conductivity


yes, that's true, but it would heat REALLY fast... and when hot, i'm not so sure what resistance it would have (i believe it rises with something like square of the temperature?)

I still think that you would go without any serious problems as long as you have good shoes and put it in neutral socket first, with one hand and let it go...

and that all with your fuses being replaced with nails... if they aren't then you can expect a few sparks and burned (switched) fuse...
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Re: paper clip in a power outlet

Postby evilbeanfiend » Wed Dec 05, 2007 10:25 am UTC

unless its at very low temperatures, or is hot enough to melt (and break the circuit) resistance should be roughly linear with temperature for a good conductor.
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Re: paper clip in a power outlet

Postby Robin S » Wed Dec 05, 2007 10:30 am UTC

btilly wrote:the resistance of the human body is quite high
but the resistance of nerves is quite low.
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Re: paper clip in a power outlet

Postby thoughtfully » Wed Dec 05, 2007 4:10 pm UTC

btilly wrote:I'm curious whether you'll apologize after you realize that you are mistaken on the facts. Power lines are generally not insulated for the simple reason that insulation costs money and they get excellent insulation for free just from being in the air.

If you doubt me, google for "power lines insulated" and read a few links. Then decide whether you feel like apologizing for your previous state of ignorance.


I use my eyes, not google. A lot of utility cabling is insulated, including the power that comes into your house. Also, the neighborhood-level stuff that comes down from the nearest substation. Go find your electric meter, and see what is running into it.

The familiar stuff, and where I see birds perched all the time, is generally insulated.

But yes, some aren't, including the cables that power electric trains, and apparantly the high-tension lines that are out of reach a couple hundred feet up in the air.

Some images I dug up, with varying degrees of clarity:
Spoiler:
Image

bare cable twisted around insulated.. are both live? or is one ground?
Spoiler:
Image

Nice pic of a transformer, and the cables connected to it.
Spoiler:
Image

Here's a nice rat's nest. I dare you to try this with bare wires, that would really be interesting :)
Spoiler:
Image


I've tried to find the relevant standards documents, but they all seem to require a fee to access.
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Re: paper clip in a power outlet

Postby arkady » Wed Dec 05, 2007 4:55 pm UTC

evilbeanfiend wrote:last time i checked 0.36 mOhms < 40-150 kOhms. which is exactly what you would expect given that paper clips are usually made from metals that have pretty good conductivity


I used stainless steel, and did actually write "greater than" when I should have written "less than".

If you take what I wrote verbitem, apparently 0.36 mOhms is much greater than 40-150 kOhms. Clearly wrong. I've corrected that now.

And yeah - the only way to really find out is to try it...but be safe, ok.
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Re: paper clip in a power outlet

Postby Marvin » Wed Dec 05, 2007 7:16 pm UTC

thoughtfully wrote:
btilly wrote:I'm curious whether you'll apologize after you realize that you are mistaken on the facts. Power lines are generally not insulated for the simple reason that insulation costs money and they get excellent insulation for free just from being in the air.

If you doubt me, google for "power lines insulated" and read a few links. Then decide whether you feel like apologizing for your previous state of ignorance.


I use my eyes, not google. A lot of utility cabling is insulated, including the power that comes into your house. Also, the neighborhood-level stuff that comes down from the nearest substation. Go find your electric meter, and see what is running into it.


that does not mean that bird's don't get roasted because wires are insulated... the point is that bird does not connect 2 wires of different potential... and as good as all high voltage wires are not insulated, it cost's a lot of money, but that it's not only problem, it adds a lot of weight...
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Re: paper clip in a power outlet

Postby btilly » Wed Dec 05, 2007 8:07 pm UTC

thoughtfully wrote:
btilly wrote:I'm curious whether you'll apologize after you realize that you are mistaken on the facts. Power lines are generally not insulated for the simple reason that insulation costs money and they get excellent insulation for free just from being in the air.

If you doubt me, google for "power lines insulated" and read a few links. Then decide whether you feel like apologizing for your previous state of ignorance.


I use my eyes, not google. A lot of utility cabling is insulated, including the power that comes into your house. Also, the neighborhood-level stuff that comes down from the nearest substation. Go find your electric meter, and see what is running into it.

The familiar stuff, and where I see birds perched all the time, is generally insulated.

I use my eyes and I see something more complex than what you do. I see a lot of different wires up there with lots of different purposes. Some insulated, and some not. It is too bad I didn't have time this morning to take a picture of the telephone pole outside of my back window, because it has a perfect illustration. So let me visually describe it.

That pole had 3 levels of wires. At the top there 2 wires. Uninsulated. At the middle level there were 3 wires. Uninsulated. At the bottom there is a whole mess of wires. All insulated. (You can see how much insulation there is from how thick the wires are.)

On the pole between the top and middle levels there was a transformer. From the 2 uninsulated wires at the top to the transformer there were 2 wires, heavily insulated. From the transformer to the middle level there were 3 lightly insulated wires. Every so often from the middle level there would be insulated wires going off to the side. And there were lots of insulated wires coming off of the bottom level.

What is going on here? Well the 2 wires on top have electricity at high voltage. As long as they are up there they don't need to be insulated. Going from there to the transformer they have heavy insulation because you don't want them to make a connection. (For instance across the top of the transformer.) The transformer steps down the voltage and the wires leading down are at a lower charge, so need less insulation. The 3 wires at the second level are uninsulated because they are in the air. The wires leading off from them go to residences and so need insulation. (If you look at what runs into your electric meter, it will be one of those.) The wires at the bottom level are not power lines at all. They carry telephone wires, cable, etc. They don't have significant power, but they need insulation because you don't want the signal to be ruined.

And yes, I've seen birds sit on all of these wires without ill effect.

Now I didn't provide you with a picture so let me find some for you. Ah yes, see http://www.themodernapprentice.com/electrocution.htm which has lots of pictures of power lines and points out the purpose of different parts of the picture. It also discusses which lines are insulated, and which aren't. And discusses in detail exactly the risks of electrocution.

You will find that even in residential areas most power lines are not insulated. And the reason that birds don't get electrocuted is because they aren't grounded. (As everyone, including me, has been telling you.)
thoughtfully wrote:But yes, some aren't, including the cables that power electric trains, and apparantly the high-tension lines that are out of reach a couple hundred feet up in the air.

Also the power lines in most residential neighbourhoods. Including the one behind my house.
thoughtfully wrote:Some images I dug up, with varying degrees of clarity:
Spoiler:
Image

bare cable twisted around insulated.. are both live? or is one ground?
Spoiler:
Image


There are a lot of cables in the air. Only some are power lines. I see no reason to believe that those cables are power lines.
thoughtfully wrote:Nice pic of a transformer, and the cables connected to it.
Spoiler:
Image

As I noted, the transformer out my back window of my house has insulated wires leading in and out of it. But those insulated wires lead to uninsulated power lines. The picture you offered doesn't show what wires those insulated wires will lead to when it is all assembled.
thoughtfully wrote:Here's a nice rat's nest. I dare you to try this with bare wires, that would really be interesting :)
Spoiler:
Image

As I noted, the wires in a rat's nest are generally not power lines. There are a lot of non-power lines up there, most of them are insulated, and there is no reason to keep them apart from each other. Hence they form rat's nests.
thoughtfully wrote:I've tried to find the relevant standards documents, but they all seem to require a fee to access.

Too bad, or you might have learned something.

But hope is not all lost. I direct you again to http://www.themodernapprentice.com/electrocution.htm which explains the same thing I did only with pretty pictures.
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Re: paper clip in a power outlet

Postby Citizen K » Wed Dec 05, 2007 8:12 pm UTC

Robin S wrote:
btilly wrote:the resistance of the human body is quite high
but the resistance of nerves is quite low.

You might find the discussion on a very related Darwin Award interesting.

Marvin wrote:that does not mean that bird's don't get roasted because wires are insulated... the point is that bird does not connect 2 wires of different potential... and as good as all high voltage wires are not insulated, it cost's a lot of money, but that it's not only problem, it adds a lot of weight...

Yes, power lines can and do kill large birds for exactly that reason (a little web search produces plenty of articles). As I understand it, they perch on the pole/support, and when they try to take off, their large wingspan touches two different wires. Zap.
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Re: paper clip in a power outlet

Postby TizzyFoe » Wed Dec 05, 2007 8:41 pm UTC

arkady wrote:
evilbeanfiend wrote:last time i checked 0.36 mOhms < 40-150 kOhms. which is exactly what you would expect given that paper clips are usually made from metals that have pretty good conductivity


I used stainless steel, and did actually write "greater than" when I should have written "less than".

If you take what I wrote verbitem, apparently 0.36 mOhms is much greater than 40-150 kOhms. Clearly wrong. I've corrected that now.

And yeah - the only way to really find out is to try it...but be safe, ok.


ah, i when i read greater then i assumed the m stood for mega (now i assume its micro).

I think i will try this next time the friends are at my house, I'll test the circuit breaker first. If you never hear back from me assume i'm dead.
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Re: paper clip in a power outlet

Postby Nullcline » Wed Dec 05, 2007 8:51 pm UTC

Godspeed, Brother. Godspeed.
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Re: paper clip in a power outlet

Postby silent man » Wed Dec 05, 2007 9:22 pm UTC

TizzyFoe wrote:ah, i when i read greater then i assumed the m stood for mega (now i assume its micro).


Actually, it should be milli, according to standard notation. micro would be µ.

Also: Be warned. The heart is a fickle organ and might decide to get lazy about its job several hours to days after you were shocked. It's not very likely but the possibility does exist.
I would generally recommend finding a science museum or something where you can play with electricity more safely. I don't say this to be a spoilsport, I would gladly help you electrify anything you care to name, but with humans it's just too dangerous.

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Re: paper clip in a power outlet

Postby Marvin » Wed Dec 05, 2007 11:13 pm UTC

Citizen K wrote:Yes, power lines can and do kill large birds for exactly that reason (a little web search produces plenty of articles). As I understand it, they perch on the pole/support, and when they try to take off, their large wingspan touches two different wires. Zap.


well... i thought more of the usual... i could also imagine a large bird being roasted flying near a high voltage lines by making them connect through air (well i can't say i saw many birds flying around high voltage lines, but i know those don't need no wire to zap something if it's close enough)

how does such a bird taste?
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Re: paper clip in a power outlet

Postby The Ethos » Thu Dec 06, 2007 12:39 am UTC

If this could be done safely, it would have been done at a hundred science frat parties before you.

As we only have stories of tragedy, this vote is for no, it's not safe.
BTW, even if you have a perfect circuit, some will always ground through you. And since the fatal amount of current through you to the ground is on the level of milliamps, don't.
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Re: paper clip in a power outlet

Postby btilly » Thu Dec 06, 2007 12:47 am UTC

The Ethos wrote:If this could be done safely, it would have been done at a hundred science frat parties before you.

As we only have stories of tragedy, this vote is for no, it's not safe.
BTW, even if you have a perfect circuit, some will always ground through you. And since the fatal amount of current through you to the ground is on the level of milliamps, don't.

*ahem*

I suffered no harm in my coat hanger experiment. That said, I would not recommend that anyone else do what I did.
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Re: paper clip in a power outlet

Postby Marvin » Thu Dec 06, 2007 1:19 am UTC

The Ethos wrote:If this could be done safely, it would have been done at a hundred science frat parties before you.

As we only have stories of tragedy, this vote is for no, it's not safe.
BTW, even if you have a perfect circuit, some will always ground through you. And since the fatal amount of current through you to the ground is on the level of milliamps, don't.


let's see... 240V, some 10Mohms? 24uA... i'd say it's survivable... (and i believe good shoes do have some 10Mohms... or am i wrong)
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Re: paper clip in a power outlet

Postby thoughtfully » Thu Dec 06, 2007 1:30 am UTC

The Ethos wrote:If this could be done safely, it would have been done at a hundred science frat parties before you.

As we only have stories of tragedy, this vote is for no, it's not safe.
BTW, even if you have a perfect circuit, some will always ground through you. And since the fatal amount of current through you to the ground is on the level of milliamps, don't.


The times I have witnessed this sort of craziness, it was performed on a concrete floor, with no flammables nearby, through a power strip, which provides an extra circuit breaker and switch action. Nobody poking things into live sockets, with fingers bare or gloved, or via pliers. No freaky sparks as you are trying to set up the experiment.

Still not a great idea, but this one of the less unsafe ways to do it.
Sorry if that spoils the flirting with death thing for you.

And yes, for god's sake, don't touch the thing with opposite ends of your body. The usual procedure is to keep one hand in a pocket. And the other one well insulated or similarly absent.

There was a cool Mythbusters on this, by the way. Dropping appliances into a bathtub.

My guess is, that the circuit breaker should shut it down before the clip melts. The math wouldn't be hard if one had the current rating for the circuit and the particulars about the clip.
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Re: paper clip in a power outlet

Postby Swivelguy » Thu Dec 06, 2007 4:55 am UTC

A lot of talk here about the resistance of humans and shoes, but any idea what the capacitance of the human body is?
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Re: paper clip in a power outlet

Postby evilbeanfiend » Thu Dec 06, 2007 10:29 am UTC

Swivelguy wrote:A lot of talk here about the resistance of humans and shoes, but any idea what the capacitance of the human body is?


hmm not a lot, a vaguely recall that a lot of power is lost from power lines from birds sitting on them and charging up, each bird only take a very small charge but there can be millions around a network each day
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Re: paper clip in a power outlet

Postby Webzter » Thu Dec 06, 2007 3:43 pm UTC

I always get shocked more than my friends and family. I know this isn't scientific, but, as a kid, I was curious why so I grabbed a multimeter and measured my resistance (held a lead in each hand and set the meter to resistance) against everyone else. My resistance is much lower than others that I tested.

For kicks, I measured after eating too and noticed that, following having a few bananas, my resistance dropped even further.

Anyway, that's my non-scientific story of bananas, multimeters, and static electricity. Oh, and by extension, my dog always braces for the shock in the winter when he comes up to be petted. He knows there's going to be a discharge when I get near him.

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Re: paper clip in a power outlet

Postby ludw » Thu Dec 06, 2007 4:21 pm UTC

I tried putting a paperclip in a power outlet once, but I held it with a wooden clothespin. The result was a nice bright spark and a blown out fuse. Kinda cool really, but I would not recommend it since it's rather stupid, not to mention dangerous =) Wasn't very old at the time..

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Re: paper clip in a power outlet

Postby Yakk » Fri Dec 07, 2007 8:08 pm UTC

First, be aware that DIFFERENT COUNTRIES HAVE DIFFERENT SOCKET VOLTAGES.

What is safe in one country will kill you in another. I'm not kidding.

Voltage lets a current ignore your insulating skin, and fry your heart on the way down through your feet.

Second, be aware that you can burn down your house if you get unlucky.

You are not a bird. You are touching the ground.
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