Power

Mechanics · 1782

Equation: P = dW/dt = F · v
Field: Mechanics
Symbols: P power, in watts · W work · t time · F force · v velocity
Year: 1782

Significance

How fast work is done. Watt needed a number to sell engines against horses and settled on 550 foot-pounds per second in 1782; the SI named its unit after him. An engine's power, not its force, sets how quickly it climbs a hill; a turbine's rating is this figure; and the same equation shows why towing at speed costs more than towing slowly.

Machines

Brushed DC Motor Induction Motor Brushless Permanent-Magnet Motor Alternator Watt Steam Engine Wind Turbine

Requires

Derivative Work

Required By

Joule Heating Hydraulic Power Inverse-Square Law of Intensity

Referenced by

equation

Derivative Hydraulic Power Inverse-Square Law of Intensity Joule Heating Work

machine

Alternator Brushed DC Motor Brushless Permanent-Magnet Motor Induction Motor Watt Steam Engine Wind Turbine

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From the Equations database in Notion, last edited 2026-08-18. This page is the row, rendered by the build; nothing on it is written by hand.