running a submerged light with exposed batteries.

[JonSidneyB]

I thought this would be an interesting picture to run exposed AAs submerged in water. The first picture is before the connectors are pushed together but everything is under water.

I pluged and unpluged the connectors while they were submerged.

A light can run from an exposed battery pack while submerged.


I did this to show something many people do not realize. Alkaline cells will function if the pack is exposed to water, even submerged.

We are also working on some improvements to the Stenlight by working on drop in reflectors by the best reflector person in the flashlight world.

[erebus]

Plain water is not a great conductor, at least of low voltages. If you tried your experiment with salt water, I don't think you'd like the results. I'm sure there's a chemist in the house who could give you a list of the substances that can dissolve in water and would make running the battery exposed a bad idea.

[JonSidneyB]

I will give it a try just in the name of science. Per Gallon of water, how much salt should I disolve into it for a good experiment?

[erebus]

You don't need to; it's been done. A lot. Here are some websites that discuss it:
http://scienceathome.cienciaviva.pt/conduti_agua_eng.html

http://www.chem.umn.edu/outreach/Conductivity.html

http://www.physics.umd.edu/lecdem/services/demos/demosk5/k5-33.htm

http://www.eutechinst.com/techtips/tech-tips25.htm

[JonSidneyB]

We know we are going to get increased conductivity of the water when the salt is added.

Electricity will mostly follow the path of least resistance. We think this is still going to work

What we expect to happen with this set up is a small amount of voltage leak but a nominal amount with the end result being reduced runtime. We think its will still not short out due to the way this is designed.

Epected results, reduced runtime and the need for a good cleanup after wards.

We are going to use seasalt for the test.

[hunter]

From personal experience I have had lights totally flood in a gyp cave and they never failed (petzl zoom and I don't remember the other one)...
The wires corroded but the light still worked fine with both the battery and bulb compartment totally flooded.

Hunter

[JonSidneyB]

yep, it does work. I am going to do the salt demo live at a meeting I think.

Lights can function if water gets in them, I think I will make sure people know this. It is better if it does not but it will work in any case.

[batrotter]

I've had my electric light totally flooded too. I use one of those Roosa or Bob & Bob lights and have had the whole battery compartment full of water for most of a day and it still works fine.