How to Make a Homemade Battery Out of Pennies
- 1). Cut a small slit into the potato. Press the penny into this slot until only a small part of the penny is exposed.
- 2). Insert the nail into the potato so that the penny and the nail do not touch each other.
- 3). Turn on the multimeter and set the measurement scale to "Volts DC." Attach the red multimeter probe to the penny. Attach the black multimeter probe to the nail.
- 4). Read the multimeter display screen. The potato battery will generate about 0.8 volts of electrical energy.
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