Rotational Power (P = τω)
Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!
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This is the rotational version of P = Fv, and it is the formula behind every engine dyno chart: horsepower is torque times rotation rate. It explains why an engine's power peaks at high rpm even after torque has started falling, and why an electric motor delivering 200 N·m at 3000 rpm (314 rad/s) is putting out 63 kW — about 84 hp.
Rotational Power (P = τω)
Where
- = Power
- = Torque
- = Angular velocity
Missing one of these? Work it out first, then come back
- Power — Power (P = W/t), Power from Force and Velocity (P = Fv)
- Torque — Torque, Torque with a Lever Arm (τ = rF sin θ)
- Angular velocity — Angular Velocity (ω = θ/t), Angular Velocity from Period