Automotive & Engines

Intermediate

Power from Torque & RPM

Engine power in kW from torque and rotational speed.

Formula

P = \frac{\tau \times N}{9549}

Variables

PPower (kW)

τTorque (N·m)

NSpeed (rpm)

Example

300 N·m at 5000 rpm: P = 1.5M/9549 ≈ 157 kW

Did You Know?

Power is torque times speed — which is why high-revving engines make big horsepower from modest torque.

automotive power torque engine

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