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Meaning: a standard unit of electromotive force that drives current | abbreviation: V

For example:

  • I need a nine-volt battery for the smoke detector.

  • We recommend a low-voltage Halogen bulb, such as a 12V bulb.

Note: Voltage measures electric force or pressure.

Origin: Alessandro Volta (1745-1827) was an Italian physicist who invented the first electrical battery, the "Voltaic pile", in 1799. The battery contained two electrodes made of copper and zinc. Volta built it after observing a frog's legs twitching during a dissection. While one scientist theorized that animals generated their own electricity, Volta had a different theory. He believed that the frog's legs twitched because two different metals touched its body. While experimenting with metals to prove his theory, he created the first electrical battery.

Quick Quiz:

If amps measure the amount of electricity used, what do volts measure?

a. the force of electricity

b. the length of electricity

c. the speed of electricty

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Contributor: Tara Benwell