Watt

watt
A 420-watt power supply
General information
Unit system	SI
Unit of	power
Symbol	W
Named after	James Watt
Conversions
1 W in ...	... is equal to ...

SI base units	1 kg⋅m²⋅s⁻³
CGS units	10⁷ erg⋅s⁻¹
English Engineering Units	0.7375621 ft⋅lbf/s = 0.001341022 hp

Electromagnetism

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The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m²⋅s⁻³.^[1]^[2]^[3] It is used to quantify the rate of energy transfer. The watt is named in honor of James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776, which became fundamental for the Industrial Revolution.

^ Newell, David B; Tiesinga, Eite (2019). The international system of units (SI) (PDF) (Report). Gaithersburg, MD: National Institute of Standards and Technology. doi:10.6028/nist.sp.330-2019. §2.3.4, Table 4.
^ Yildiz, I.; Liu, Y. (2018). "Energy units, conversions, and dimensional analysis". In Dincer, I. (ed.). Comprehensive energy systems. Vol 1: Energy fundamentals. Elsevier. pp. 12–13. ISBN 9780128149256.
^ International Bureau of Weights and Measures (2006), The International System of Units (SI) (PDF) (8th ed.), pp. 118, 144, ISBN 92-822-2213-6, archived (PDF) from the original on June 4, 2021, retrieved December 16, 2021