Lemon battery without copper and zinc metals

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fog37
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Hello,

I have seen a video online that shows how a LED can be lit using a single lemon without using a copper and a zinc nail. They simply stick the LED into the lemon.

What does that work? I know the lemon contains the electrolyte but don't we always need to dissimilar metals for the battery to work?
thanks!
 

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I think you need a lime for it to work.:rolleyes:
 
yeah, true. But why?
 
fog37 said:
yeah, true. But why?

It was a joke, the video is a poor fake.
 
If you wanted to fake it, could you plate one leg with zinc? It would look silver on a video and maybe pass for an "untreated" LED. The anodic index of silver solder is the same as copper according to the table here:
http://www.engineersedge.com/galvanic_capatability.htm
 
Let say you had a single cell made with a magnesium/copper plated tiny surface reaction area legs LED that might give 1.6 volts (the penny/nail open voltage is about 0.9) open circuit and drop to half that voltage value with a few micro-amp load because of high internal resistance. Would that work to light an LED?
1883Fig10.gif
 
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fog37 said:
I have seen a video online that shows how a LED can be lit using a single lemon without using a copper and a zinc nail. They simply stick the LED into the lemon.
Possibly there could be concealed wires or a battery buried inside the fruit?
 
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NascentOxygen said:
Possibly there could be concealed wires or a battery buried inside the fruit?

It is definitely a shoop. I can tell from the pixels. Third one from the left has shifty eyes.

BoB