I read that distilled water doesn’t conduct electricity, so If I replaced the 70% or so of my body’s water with it, would I be immune to electricity? Is there a way to remove all of the electrolytes from my system and still live?
first off, our bodies are made up of mostly salt water, which is a good conductor all by itself (lots of Na and Cl ions to help those little electrons just zip around). Without the proper level of salt in your body you get sick and die. You would expire long before purifying your system enough to stop conducting. Also the nervous passageways in your body are designed to carry electrons around. so even if you survived the ‘purification’ process, you’d still be a pretty good conductor
you can build a tolerance to shocks. but don’t do this, you build this tolerance by damaging nerves. and if you do it wrong/too much you could again, die.
I don’t know you, but I don’t think you deserve to die (though the darwin awards might find it amusing) so please don’t try to build an immunity to electricity.
There are a few problems with this scheme:
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It’s true that *pure[\i] water doesn’t conduct electricity, but absolutely pure water isn’t easy to get (or keep). A tiny amount of impurities in the container will spoil the insulating properties of water. Replacing 70% of a container of water with pure water wouldn’t even be close.
Distilled water from a store also isn’t even close. -
Removing all electrolytes from your system would be like removing all the wires (and traces on circuit boards) from your PC - it’s not going to work without them.
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Many body processes are electrically stimulated (such as heartbeat, neural activity, etc.) I think you’d want to maintain some electrical conductivity to keep those going
Your best bet is covering your skin with some insulating material.
Arjuna34
Electricity follows the path of least resistance. Our skin actually has a somewhat high Ohm rating (I can’t recall the actually value but some physics books contain it, try Tipler for a cite), which is why electricity burns you (resistance to electrical flow generates heat, see also stove, oven, electric blanket, etc etc etc)… but I’m getting off topic…
since your skin has a decent resistance to electric flow, if you covered yourself in a good conductor and kept it grounded the electrons should happily run along your conductive suit and down to ground.
Again… don’t try this… doing it wrong could once again lead to a slight case of death. and like I said, I doubt you deserve to die (but hey I’ve been wrong before 
Heh!
I don’t recommend it!
Also to add a little, popular opinion is has it that water conducts electricity well, that is not true, the purer the water the less well it conducts.
I’ve been out and done firefighting training during my time in the navy and used salt water directly onto 440V busbars without any problem, it took the instructors a lot of persuasion to get me to do it.I don’t rmember the exact distance but it must have benn around 4 or 5 feet away and I was soaking wet and holding a brass hose nozzle at the time.
The reason that being wet and clutching live conductors is so dangerous is that it increases your contact area .Dry hands only contact where they touch but water bridges the gaps beneath things like the creases in your hands, and of course the distance is extremely small so that the resistance of the water is negligeable.
Does anyone else read “Smithsonian” magazine (if you don’t I highly suggest getting a subscription, well worth the money)… anyhow… sometime in 1999 or 2000 they did an article on a lightning research institute (if someone could help out with the cite I’d be indebted to you)… one of the touristy type features of this place was the lightning chamber. you get locked in a metal spheroid and lifted off the ground, they then release huge bursts of electricity through the ball you’re sitting in so you can ‘watch lightning’ from the inside…
I have no idea what possible purpose this post serves, but it’s a cool idea.
What bobo said, but I also want to add that it does not take a spectacularly large amount of electric current to kill. One milliamp is sufficient. So, it is entirely possible that you can make a mistake, misestimate Ohm’s Law (happens all the time, at least when I was in electronics school), and do yourself in.
If you do decide to try this stunt, what you’d basically be doing is setting up a circuit from your hand through your nervous system, through your heart (path of least resistance, remember?), and back to your other hand. The muscle in your heart is designed to react to electricity, which is how it beats in the first place. What the electric shock would do is throw your heart into a condition called fibrillation, in which the heart beats so quickly and irregularly that the beats are useless. And, no, you don’t build up an immunity to this over time.
In this column, Cecil goes into greater detail on what happens to someone who’s electrocuted. See if this doesn’t change your mind. If not, make sure someone lets us know so we can start the paperwork process for a Darwin Award.
Robin
Bobo
As it happens your idea is not as mad as you think.
My next door neighbour is a grid lineman. He is one of those intrepid people who gets into a carrier which is lifted by a helicopter on very long and well insulated cables.
The carrier is hooked onto the grid wires and he works on 475KV cables live!!! :eek:
He wears what appears to be a chainmail suit that acts as a Faraday cage, electricity can flow around but not through him.
I bet he has one hell of a wait when the helicopter fails and can’t lift the carrier down.
KV, just have to say, this post made me smile. As bobo said, there’s no way to accomplish what you suggest. This is just a WAG, but I think you’d live longer after removal of your brain, heart, lungs and all the blood in your body then if you removed all the ions in your body. For the record, I recommend neither.
Ionic substances are fundamental to our physiology. Without a couple of years of physiology under your belt, exactly why this is the case, is pretty difficult to understand. This probably isn’t the right forum for a detailed discussion on the topic, so I won’t even try.
BTW, the 70% water figure you cite is referring to 70% pure, distilled water. The remaining 30% is made up of ions, proteins, carbohydrates, fats and other organic molecules.
Of course, no bodily fluid is composed of pure water. But when calculating the fraction of our body mass contributed by water, it’s pure water that’s in the equation.
I disagree with this statement. The capacity of a neuron to conduct an impulse is inextricably linked to it’s ionic physiology. So no ions=no impulse conduction. Additionally, the manner in which impulses are conducted by neurons bears little resemblance to electrical conduction in wires. In a living neuron, sufficient electrical stimulation does initiate the propagation of an electrical impulse, but the impulse is actively manufactured by the neuron. It is NOT a passive flow of electricity through a specially designed low resistance channel. I’d be surprised if during electrocution, a disproportionate amount of current flows through neurons. Within a frame of reference, the internal ionic consistency of most bodily tissues (nerves, heart, muscle, though probably not fat tissue), is identical. Therefore, assuming ionic consistency is the major determinant of resistance, I’d predict that their electrical resistances are similar as well.
Casave, I’ve heard of this, but my impression of how it works is different from yours. The function of the suit is to make your brave buddy eqipotential (same voltage) as the power line. Having the wire mesh all around him ensures a uniform distribution of the electrical charges. Electricity is only hazardous when flowing, and it will only flow from high potential (voltage) to low. The insulated, suspended platform isolates him from ground (read: low potential). The suit ensures that no potential gradients develop in your pal while he’s working. The whole system is designed to create a no flow (static) situation.
I’ve talked to a lineman who wore one of those copper suits, and was helicoptered up to work on approx. 500kV lines (in England).
In addition to choosybeggar description, I think the suit also helps carry the static current when the lineman 1) touches the 500kV line for the first time, and 2) touches a grounded object for the first time, after he’s done working.
Arjuna34
Insulating your shaved scalp & wrist (which is where I believe they will be attaching the electrodes) with some of that high dielectric constant lacquer (sorry I forget the brand name- been out of consumer too long) would raise your contact resistance well into the megohms but that wouldn’t work either, because you’d essentially be turning yourself into a living (but only temporarily) capacitor. As soon as he warden throws the switch, your body would draw charging current that would initially be maximum according to ohm’s law as applied to reactive circuits. After an short amount of time equal to 5RC the charging current would expire, but not before you did.
You’d also be subject a huge transient voltage spike, but it’s the current that will terminate you.
Okay, I’ll change my OP a little bit… Does a dead body conduct? I mean after it’s had a little while to decompose. Say a week or so.
Attrayant
Not too sure about that.
If you could get your impedance high enough the current flow would be so small as to be fairly safe.
Human body capacitance is very small and so would draw a tiny amount of current, I have seen it quoted somewhere at around 110pF for a model of the human form, usually taken as a 1 metre sphere but you would need an electrostatics physicist to confirm that.
The electrodes are attached some distance from each other and so that would tend to reduce the body capacitance
Human capacitance is a pretty serious subject any semiconductor manufacturer will attest to that as will hospital instrument techies too.
Just what sort of fiendish scheme are you planing, KV?. First, it was sucking the ions out of somebody, and now we’re juicing up decomposing flesh?
I believe you’re referencing the Lightning Cage* at the Boston Museum of Science, home of the world’s largest air-insulated Van de Graaff generator!. Here’s the museum’s web page on the thing with some impressive pictures. http://www.mos.org/sln/toe/cage.html The last time I was there, it closed. darn.
*note: While the it is a cage, it is definitely not a Farraday cage, but rather a cage that demonstrates the Skin Effect. http://www.mos.org/sln/toe/skineffect.html
Sure! Everything is conductive to some extent, with the possible exception of a total vacuum.
How good a material at conducting is depends on its physical properties. Engineers refer to something called a dielectric constant when they need to plug an exact number into a formula to arrive at a value for electrical components’ specific properties. Here is a list of the dielectric constants of some commonly used dielectric materials:
Air 1.0
Balsa Wood 1.4
Fir (wood) 2.1
Carbon Tetrachoride 2.2
Vaseline 2.2
Paraffin Wax 2.25
Mohogany 2.4
Rubber 2.5
Paper 3.3
Glass 4.0-7.0
Bakelite 5.0
Mica 5.5
Formica 6.0
Porcelain 6.0
Celluloid 6.2
Ethyl Alcohol 28.0
Distilled Water 78.0
These numbers have no real significance by themselves because they are not units of measurement, but mathematical constants. However looking at them side by side allows you to see the relative strengths of one compared to another.
The conductivity of a mass depends not only on what it’s made from, but also its size. The resistance of a sample of material is directly proportional to its length and inversely proportion to its cross sectional area:
L
R = ð ---
A
Where R is resistance in ohms, L is the length of the current path in meters, A is the cross sectional area in m² and ð is the constant of proportionality between R and L÷A.
The constant of proportionality is called resistivity or specific resistance, and because I’m getting real tired of vB coding, boils down to:
ð = ohms × meters
Silver (the best of all mundane conductors) has a ð of 1.63 × 10[sup]-8[/sup]. Annealed copper (the 2nd best) checks in at 1.72 × 10[sup]-8[/sup]. Brass is 6.8, lead 22.0 and mercury about 96 (all × 10[sup]-8[/sup]).
For insulators we have ð values such as:
Paper 10[sup]10[/sup]
Mica 10[sup]11[/sup] - 10[sup]15[/sup]
Nylon 8 × 10[sup]12[/sup]
Porcelain 10[sup]16[/sup]
Teflon 10[sup]17[/sup]
And so on.
Calculate the direct current flow through any resistive material with the simple application of ohm’s law:
I = V ÷ R
So you see that even with Teflon, you can get 1µA (1 microamp or 1 × 10[sup]-6[/sup] amps) of current to flow as long as you apply 1 × 10[sup]12[/sup]V (one trillion volts) across it.
Now young man, what exactly are you planning on?
With regard to the capacitance between semicinductor junctions you’re talking about Miller Capacitance, or interelectrode capacitance (boy I’m getting tired of typing that word!).
With regard to the KV’s impending exocution I am thinking more along the lines of the following: The human body is actually a pretty decent conductor, but in a circuit made up of excellent conductors like copper the body will act more as the significant resistance. A thin coating of a insulating lacquer would form the dielectric of the capacitor (the damp skin being one plate, the electrode being the other), one at each electrode. That results in the circuit as follows:
+V -----||----- (KV’s Twitching Corpse) -----||----- Ground
I considered the body as the resistive part of the circuit, not the dielectric. That’s why I mentioned the voltage spike when the switch is thrown. As the charge begins to die off, the resistive voltage spike decays. Exactly how much current will flow during this period is a matter of almost pure speculation & will vary widely depending on all the standard parameters (voltage applied, strangth of dielectric, etc.).
We can only hope that KV takes careful measurements & records the whole thing on VHS.
I will be sure to tape it, might even fork over the 2 million dollars and air it during the super bowl today.
cool thanks… I’ll have to take take the T to the museum, I had no idea there was one of these here in boston… thanks evilhanz