What is the unit of power in the International System of Units?

The unit of power in the International System of Units (SI) is the watt. Power is defined as the rate at which work is done or energy is transferred. One watt is equivalent to one joule per second. This means that if one joule of energy is transferred or converted in one second, the power output is one watt.

Understanding this concept is essential as it relates to various principles in mechanics and energy transfer. For example, when considering the performance of machines, electrical devices, or even human activities, power provides a measurement of how quickly work can be accomplished.

Joules, while a unit of energy closely related to power, do not measure the rate of energy transfer and thus describe a different aspect of mechanics. Newtons are the units of force, representing mass times acceleration, and pascals are units of pressure, defined as force per unit area. Each of these units serves a specific purpose in physics, but only watt specifically quantifies power.