volt (vōlt) Pronunciation Key
The SI derived unit used to measure electric potential at a given point, usually a point in an electric circuit. A voltage difference of one volt drives one ampere of current through a conductor that has a resistance of one ohm. One joule of work is required to move an electric charge of one coulomb across a potential difference of one volt. One volt is equivalent to one joule per coulomb. See also Ohm's law. |
The unit of electromotive force, the volt measures how much “pressure” there is in an electric circuit. The higher the voltage, the more electrical current will flow in the circuit.
Note: Ordinary household outlets are usually rated at 115 volts, car batteries at 12 volts, and flashlight batteries at 1.5 volts.
volt
unit of electrical potential, potential difference and electromotive force in the metre-kilogram-second system (SI); it is equal to the difference in potential between two points in a conductor carrying one ampere current when the power dissipated between the points is one watt. An equivalent is the potential difference across a resistance of one ohm when one ampere is flowing through it. The volt is named in honour of the 18th-19th-century Italian physicist Alessandro Volta. These units are defined in accordance with Ohm's law, that resistance equals the ratio of potential to current, and the respective units of ohm, volt, and ampere are used universally for expressing electrical quantities. See also electric potential; electromotive force.
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