The watt (symbol: W) is the unit of power in the International System of Units (SI). It is named after the Scottish engineer James Watt, who made significant contributions to the development of the steam engine.

The watt is defined as one joule per second, where a joule is the unit of energy. Mathematically, it is expressed as:

Watt (W)=Joule (J) /Second (s)

In equations, you may see it written as:

P=W/t

where:

P is power in watts,
W is energy in joules,
t is time in seconds.

This formula illustrates that one watt is equivalent to one joule of energy expended or transferred per second.

Power is a measure of the rate at which work is done, or energy is transferred or converted. In everyday terms, it is used to quantify how quickly an electrical device uses or produces energy. For example, a 60-watt light bulb consumes energy at a rate of 60 joules per second. Similarly, a 100-watt solar panel can generate 100 joules of electrical energy every second under ideal conditions.

Common multiples and submultiples of the watt include kilowatts (kW) and megawatts (MW), which are equivalent to 1,000 and 1,000,000 watts, milliWatts, microWatts, 0.001 and 0.000,001 Watts respectively.

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