A potato delivers a higher power (more Watts) than a lemon in both parallel and series circuits. The potato always produced more power than the lemon. This means the potato is a better battery than the lemon.

A lemon battery is a simple battery often made for the purpose of education. Typically, a piece of zinc metal (such as a galvanized nail) and a piece of copper (such as a penny) are inserted into a lemon and connected by wires.

Directions

1. Set the multimeter to measure DC voltage (V with a straight line).
2. Hook two alligator clips from your leads to the two electrodes.
3. Measure the voltage from your lemon cell.
4. Now set the multimeter to measure current (A with a squiggly line: mÃ/Ã).
5. Measure the current of your lemon cell.

Make sure all your wires are securely connected to the alligator clips and then to the metal. If the circuit isn’t tightly wired, the electricity can escape. The metal in the potatoes must be copper and a nail covered in zinc. A steel nail will not work and other wire won’t conduct electricity as well.

Stick the pennies in the slits you cut into the potato halves. Stick that second nail into the other potato half. When you connect the two loose ends of the copper wires to the light bulb or LED it will light up [source: MathinScience].

about 1.2 volts

A single lemon produces about 7/10 of a volt of electricity. If you connected two lemons together, you can power an inexpensive digital watch (uses about 1.5 volts). (Use a length of thin, flexible wire to connect the silver wire of one lemon to the copper wire of the other lemon.

A potato clock runs by converting chemical energy into electrical energy, which is then used to power a clock. The potatoes, in combination with zinc and copper strips (which act as electrodes), act as a battery. Most people aren’t aware that this is possible, which is what makes it so interesting.