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Q & A: Why won’t my lemon battery work (again)?

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Most recent answer: 10/22/2007
Q:
I am making a lemon battery for a science and would like to know if you can help. I have checked many sources, including yours, and have followed the tips with no luck. I am presently using 3 lemon halves connected in a series circuit using a penny and a galvanized nail in each half as electrodes to light up a small 1.1 volt light bulb. I have checked my circuit with a 1.5 volt AA battery and electricity is following and lighting the light bulb. I also have tested my lemons with a volt-meter but I can’t quite understand what the volt-meter is telling me. I can get the needle to move but I don’t understand what it means. I recently went Radio Shack and talked to someone and they explained to me how to use the volt-meter. I proceeded to follow the man’s directions and now can get nothing out of the volt-meter with the lemons, but the AA battery works fine with the meter. Can you tell me what I am doing wrong with the lemon battery and the volt-meter? I appreciate your assistance with my project. Thank you for your time.
- Jonathan
New York, NY
A:
Jonathan -

If you haven't read it yet, check out the answer to the question "Why won't my lemon battery work?" under the Electricity and Magnets: Circuits section of our answers list. If you can't get any result at all on a voltmeter, you may want to try using solid copper and zinc, rather than pennies and nails. Many pennies (especially newer ones) actually have very little copper in them (and actually have a lot of zinc in them, too), so that may be part of your problem. Also, the nail you're using may not have very good quality zinc in it, but you can get good zinc strips from the casing of old carbon "D" batteries. Good luck!

-Tamara

(published on 10/22/2007)

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