The **watt** abbreviated **W** is the International System of Units SI standard unit of power energy per unit time the equivalent of **one joule per second.**

The **volt** (symbolized V) is the Standard International (SI) unit of electric potential or electromotive force. A potential of one **volt** appears across a resistance of one ohm when a current of one ampere flows through that resistance.

An **ampere** is a unit of measure of the rate of electron flow or current in an electrical conductor. One **ampere** of current represents one coulomb of electrical charge (6.24 x 10^{18} charge carriers) moving past a specific point in one second.