Automotive & Engines

Intermediate

Power-to-Weight Ratio

Engine power divided by vehicle mass — the key to acceleration.

Formula

PWR = \frac{P}{m}

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Variables

PWRPower-to-weight (kW/kg)

PPower (kW)

mMass (kg)

Example

150 kW, 1200 kg: PWR = 0.125 kW/kg

Did You Know?

A Bugatti Chiron and a superbike can have similar top speeds because both maximise power-to-weight.

automotive power acceleration

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