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Does electricity flow differently or better through salt water, sugar water, Fantastik, , orange juice and milk?

I want to perform a science experiment for my 4th grade science fair, and my teacher signed off on my problem/question. It's like the others here except I am not thinking about using household electricity In order to keep this experiment safe yet effective, should I get a large battery and run a wire into the liquid? If so, should we then run another wire out of the liquid to a lightbulb? I realize the wires shouldn't touch...but would this even work enough to light the bulb? I found the discussion here about electricity and water and thought I would ask the experts. Thanks for your time.

Liam R
student - Chatham, New Jersey
February 9, 2008

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I have not done the experiment, Liam, but my bet is that none of these liquids will be conductive enough to allow you to power a lightbulb. If you have a resistance meter ( ⇦ this on eBay or Amazon [affil links] ) you can measure the resistivity of these various solutions though, and rank the liquids by their resistivity.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 12, 2008

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I am not in favor of a 4th grade student messing around with household electricity. It CAN kill some people in the right conditions.
Batteries do not deliver a constant voltage over a long period of time. Consider using a small and cheap 6V battery charger ⇦ this on eBay or Amazon [affil links] .

You need to do some homework on resistance and resistivity.

You need to have a method of having non reactive electrodes (stainless or titanium should do) of a constant size and distance apart. They need to be well cleaned and very well rinsed between each measurement. This may, repeat may, require sanding with very fine wet/dry sandpaper. Do not try to use the cheap yellow /red stuff. Garnett is fine for wood, but not for doing wet sanding.

Remember, if you use a 6 volt power source, you will need a 6 volt bulb.

James Watts
- Navarre, Florida
February 13, 2008