In the field of physics, the Watt (often denoted by the symbol ‘W’) can be defined as the derived unit of power. As per the International System of Units (often abbreviated to SI), one Watt of power is equal to one Joule of energy consumed in one second. The Watt can also be used in order to quantify the rate at which energy is transferred. The SI unit of power is named after the Scottish inventor and chemist James Watt. The rate of work being done is said to be 1 watt when an opposing force of one Newton is applied to a body and its velocity is held constant at one meter per second. The SI base units of the Watt are kilogram.meter2.second-3 (or kg.m2.s-3). It is important to note that the watt is not the same as the watt-hour.