Science Buddies: "Ask an Expert"

Need to help my daughter figure out how to run a raido from veggie power. The radio we purchased uses 2 AA batteries. I have helped her make a veegie battery that is at 3.80 volts but it will not work the radio. Does it matter what gauge of wire you use to jump from the radio to the battery.

Hi abreu,

I'm not sure why the radio isn't working. My hunch is that the veggie battery is not providing enough current. Have you tried connecting batteries in parallel as in Figure 2 in https://www.sciencebuddies.org/science- ... p029.shtml

Per gauge, If you consult:

http://www.thelenchannel.com/1wire.php

it does not appear that the wire is adding much resistance to the circuit, since the chart gives resistance per 1000 ft or per kilometer.

The surface area of the electrodes and how dried out or wet the fruit/vegetable is will significantly affect the amount of current that the cell can provide. If you have a 1000 ohm and 100 ohm resistor, you can use them as load resistors and measure measure the voltage across each resistor with your meter and compare it to the open circuit (no load resistor) voltage. I suspect that you will find the voltage drops considerably when a load is applied.

The wire has to be 3 feet of 12 guage wire.