Watt (W)

Modern equivalent

1 Joule per second

Calculates structural power expenditure matching Volts multiplied by Amperes.

Named after steam engine pioneer James Watt, the watt is the SI unit of power, measuring energy transfer rates in electrical, mechanical, and thermal systems. Though Watt is remembered for refining the steam engine, the unit bearing his name was adopted by the British Association for the Advancement of Science in 1882, deliberately chosen to bind the emerging science of electricity to the established mechanical engineering tradition that had built industrial Britain.

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