I have never seen this demonstration before. Water running through two small open cans into a larger metal collection container wired together to create 10,000 to 15,000 volts. Is it an accumulation of static electricity? If someone knows what is happening I would love to hear about it! Via: Zedomax |
February 28th, 2007
i have seen this a while back on this one site, so i dug through my favs and i found it
http://www.rmcybernetics.com/projects/experiments/experiments_kelvins_thunderstorm_electrostatics.htm
enjoy:)
February 28th, 2007
Thanks Seesoe, that was a great explanation. It says that it works better with purified water but I wonder if the rain water from the roof would work? It would be interesting to generate some electricity every time it rained…
February 28th, 2007
This was demonstrated in on of my introductory physics classes a few years ago. As seesoe mentioned, this is Kelvin’s Thunderstorm. Here’s another link explaining the phenomenon: http://www.newphys.se/fnysik/3_1/kelvin/index.html
February 28th, 2007
oh cool, we will have to post that on zedomax.
March 1st, 2007
Thanks Steve
March 1st, 2007
So how much power is acheived from this? He said that it was a ‘great battery’.
March 1st, 2007
I think this work by running water through the cans which causes static charge which then is transfered to the wires into electrical energy
March 1st, 2007
My brother once did something like this for a school science project but instead of using the paint cans A & B he used small copper circles and it was supposed to build a charge on the wires enough that a drop of water would float in the air because of the static charge. He could never get it to work, but nether less a interesting experiment.
March 2nd, 2007
i have to try this one - it looks like a good weekend project. i already have 4 cans out the recycling bin and a plastic jar to make the takn at the top :). but i don’t know how well it will work with out pure water. and i like the drain-pipe idea. anyone know how to turn 10,000+ v change into a useful supply?
March 3rd, 2007
Zedomax, I watched the video you have linked and it was very interesting, I am guessing here that the static charge is actually provided through the the transfer of a eletrostatic charge (electron transfer) between the water running throught the barrel and plastic tubing. This would allow the water to transfer it’s charge from the friction with the tubing - through the air (made easier with a humid atmosphere”water”) to the smaller (insulated) cans allowing the charge to build up till it can bridge the gap between the two metal rods.
-Ryan
also look here for more info -
HowStuff Works - Static electricity
http://science.howstuffworks.com/vdg1.htm
March 3rd, 2007
Thanks for the info Flyinrhino1, you have a cool site there!
March 6th, 2007
This is called a Kelvin Water dropper. It is static electricity. The biggest problem that most people encounter is not insulating it enough. If it has even a slight connection to a ground or big piece of metal it will not work. Someone said they used a coil of wire for the top rings, this will not work, well at least not very well, the bigger the surface area on the inside of the rings the more static charge will be built up. When I built mine it was one too large blocks of wax, just to keep it insulated.
March 9th, 2007
This is based on a quite old Scientific American article…over 20 years ago if I remember right.
March 10th, 2007
You should also check this:
http://youtube.com/watch?v=4TgmOUWkkIk
its another of Walter Lewin’s
March 13th, 2007
i am not quite shure but i think that somehow the cans are getting charged with static electricity. the water is spreading gradually because the cans are becoming more charged, and water is a conductor therefore being attracted to a charge. once the cans are charged enough, the spark is created by the electron transfer between the two poles, making them neutral once again. and the process just repeats itself over.
March 15th, 2007
He sounds like a cross between Einstien (pretend, okay?) and Bartok (Anastasia.) It’s very cool, but I cant help but giggle.
March 20th, 2007
A very thorough explanation:
http://amasci.com/emotor/kelvin.html
April 3rd, 2007
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April 30th, 2007
Thanks for the link Jeff. Thats pretty nifty. Is there a way to harness that energy or is it basicly pretty useless?
May 2nd, 2007
ya just plug it into a rechargeable battery…or it can be a huge tazer!!!
October 11th, 2007
What hapend if you put several other cans down can A and can B and wire them to the C and D cans in the correct way, that will produce more power?
February 17th, 2008
The paint can above each bucket is charged oppositely to the charge in that bucket.
The paint cans serve to attract charges of the same polarity to the bucket under it and the opposite polarity of the other bucket, thus accumulating charge in the bucket under it, and attracting opposite charge to the other bucket, which builds the charge in both buckets.
This accounts for the spreading of the stream as the charge gets stronger because the charge in the water tends to make the droplets repulse each other and spread out.
What I cannot say for sure is the genesis of the beginning charge that starts the whole thing, I expect it is random, and that once a charge begins one bucket stays positive and one negative because the discharge is not total.
This is a great experimental way to segregate the charges in water. Water in a steady stream is a conductor but it breaks the conduction by forming into droplets and the tendency for the gravitational force to overcome the static electric force as it falls into the buckets, finally enough charge to repulse from its own bucket and attract to the other bucket.