Volt

The volt (symbol: V) is the derived unit for electric potential, electric potential difference (voltage), and electromotive force. The volt is named in honour of the Italian physicist Alessandro Volta (1745–1827), who invented the voltaic pile, possibly the first chemical battery.

Description

The volt is a measure of electric potential. Electrical potential is a type of potential energy, and refers to the energy that could be released if electric current is allowed to flow. An analogy is that a suspended object (a mass) that is said to have gravitational potential energy (as a result of a gravitational field), which is the amount of energy that would be released if the object was allowed to fall.

In alternating current, the voltages increase, decrease and change direction at regular intervals. As a result, voltage for alternating current almost never refers to the voltage at a particular instant, but instead is the root mean square (RMS) voltage, which is a way of defining an effective voltage when calculating power (RMS voltage × RMS current). In most cases, the fact that a voltage is an RMS voltage is not explicitly stated, but assumed.