Alkaline Batteries & Light Bulbs

[Sarabob]

My son is doing an experiment to see how long different sizes of batteries last (AA, AAA, C, D). We originally thought he would be able to use copper wire to connect the battery to a light bulb & time it to see how long it took for the battery to burn out. Turns out we were wrong, at least with what we've tried. I would welcome any suggestions as to how to connect the 2 so he can test each battery with the same output source.

[barretttomlinson]

Hi,

Copper wire should work better than almost anything else. What is the problem you are having?
Does the lamp not light? If so the wire may have insulation on it. Some copper wire has a varnish coat on it to insulate it- that insulation is rather easily removed by scraping with a knife. If the connection makes the lamp light but the connection comes loose when you put it down, you may be able to tape or solder the connections in place. Most flashlights use a spring to maintain the connection by putting pressure on the wire to bulb/battery connections..

I hope this helps. Good luck with the detective work!

Barrett Tomlinson

[Craig_Bridge]

You should be able to come up with an appropriate light bulb for the battery. A PR1 flashlight battery is designed to be powered by a single 1.5v battery cell (rated at 2volts 950mA). A PR2 is rated at 2.38volts 500mA. A PR4 is rated at 2 volts 270mA.

To estimate how long a battery will last, take its mAhr rating and devide by the current the bulb uses to get the number of hours. A typical AAA battery has a rating between 900 and 1100 mAhr and a AA battery can be as high as 3000 mAhr.

Batteries have a shelf life. Just sitting around they slowly loose their ability to provide power.

Please provide some additional details for the problem(s) you are having so that we are able to better help you.