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Power⚠ unverified

Physics / Mechanics · Compute average power as work per unit time

Parameters

InputSymbolUnitDefaultDescription
workworkJ1.0Work done or energy transferred
timetimes1.0Time interval over which the work is done
OutputSymbolUnitDescription
resultPWAverage power, in watts (W)

The science & history

Understanding the Parameters

Derivation (Approaching a Proof)

Power is defined as the time rate of work (or energy transfer):

$$P = \frac{dW}{dt}.$$

For constant power over an interval, $W = P t$, so $P = W/t$. Connecting to mechanics: $dW = \mathbf{F}\cdot d\mathbf{r}$ ⇒ $P = \mathbf{F}\cdot\mathbf{v}$.

History

James Watt popularised power as a practical engine metric (horsepower); the SI watt honours him. Mechanical $P = W/t$ and electrical $P = VI$ share the same unit by design of the SI.

Related Concepts: Work Constant Force, Power From Force Velocity, Kinetic Energy, Watt's Law, Motor Power

Notes: Registry calculator power (unverified). Average power for constant work rate. Distinct from electrical cards named Power Factor, Motor Power, etc.

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