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Can the human body be used as a battery?

My son and I are working on his science fair project which is to light a light bulb using a piece of copper pipe, a piece of galvanized pipe, and two wires with alligator clips to connect the light bulb.  The theory is that holding the two pipes in ones hands, the  body will create enough current to light the bulb.  We have not had any success yet.  Even wetting our hands had no noticeable affect.  Any ideas?  Is this a plausible theory?

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blackhol110 months ago

You must put yourselves in series, get 2 pieces of copper and 2 of zinc. In one hand hold onto the copper and zinc in the other, the other person does the same. Except reverse the order of copper and zinc for the other person. Next touch the zinc to the copper of the other person, the copper left open in the first persons's hand and the zinc in the second person's hands is your dc output. Try that. If it does not work, email me at blackhole2001@outlook.com.

NachoMahma7 years ago
.  Not really. Skin resistance is too high to light even an LED without the danger of killing yourself. Blood doesn't make a very good battery electrolyte. A mV meter might work.
Suggestion: Reduce resistance by putting the two contacts closer together -- opposite sides of one hand, for example. After you've done that, increasing contact surface area might help.

... though I expect you would get more current from induction (the wires picking up stray magnetic fields from the AC wiring around you) than from the human battery.


I did this yesterday with a nickel and a penny held in opposite hands. I got about 35 mV. A fun thing to do is to have two subjects, one holding a penny and the other a nickel. When they hold their free hands, you get voltage, and when they let go, you don't: a hand-holding switch.
Also, polish the two contacts, so there isn't corrosion/crud/varnish on the surface inhibiting the reaction.

Also... A battery works by ion transfer. I doubt you'd get enough here to be an issue, but you might want to calculate which direction that's going, how many atoms of metal you're driving into your sweat and possibly into your cells, and whether that's a good thing. (Extra credit item, obviously, IF you make it work.)
This isn't really using the BODY as a battery, just a wet electrolyte though isn't it ?

Steve
Yeah, but that seems to be what they were trying to do...

Personally, I'd either change the description of the science fair experiment and build a skin galvanometer (which can be plenty entertaining; plans are available from many sources and it's actually not bad as a toy lie detector), or find some completely different project. Though an experiment that fails is, in fact, a useful data point.
ANDY!6 years ago
try getting hit by lightning!
jeff-o7 years ago
The movie The Matrix lied to you.

Try MahavishnuMan's idea, I think that has the greatest chance of success.


I have an idea.  Saliva seems more successful than skin contact in yielding some electricity.  Make a "cottonmouth cell" by layering a copper screen, a thin cloth, and an aluminum screen (in that order).  Then, roll them into a cylindrical shape, fix the alligator clips to each screen, and place it in your mouth.  Make several of these and wire students from his class in series to see just how much electricity you can make from a human spit battery.

As Fram stated, this would still not be sufficient to light a bulb (although enough students in series might yield enough to light a small, low-power red LED).  Your best bet is a voltmeter.
framistan7 years ago
Instead of trying to LIGHT A LIGHTBULB... try connecting your wires to just a DIGITAL VOLTMETER set to volts setting.  The digital voltmeter only requires MICROAMPERES of electricity to give a display.  You might even get a few VOLTS out of it???  Which will look impressive on your VOLTMETER... but will not be capable of doing any actual WORK such as lighting an led or etc.  You can buy a digital voltmeter at harbor freight tools for three dollars.  Radio shacks are more expensive.
mathews7 years ago
You may not be able to power the bulb, but you could show some conductivity through a human body.

If you apply a small AC signal to one point, you should be able to measure it at another with a high gain, high input impedance amplifier.
Applying a volt to the body would not show that it was a battery, it would only demonstrate conduction thru the human body.
Re-design7 years ago
The human body does generate some electricity but not any that you can use to demonstrate lighting a light bulb.  Each nerve and muscle works by electrical conduction.  Those are tiny points of pos. and neg. electricity.  They can be measured by very sensitive electric instruments like EEG and EKG machines.  These take very small voltages and amplify them many times to move meters and writing instruments.

Even if the voltages were higher the left hand would be as positive. as the right hand and there would be no current flow. 
Well you can, but you really won't like where you have to shove the electrodes....