Automotive & Engines

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Aerodynamic Drag

Air resistance a car must overcome, rising with speed squared.

Formula

F_d = \tfrac{1}{2}\rho v^2 C_d A

Variables

F_dDrag force (N)

ρAir density (kg/m³)

vSpeed (m/s)

C_dDrag coefficient

AFrontal area (m²)

Example

ρ=1.2, v=30, C_d=0.3, A=2.2: F_d ≈ 356 N

Did You Know?

Drag dominates fuel use above ~80 km/h, which is why economy plunges on the motorway.

automotive drag aerodynamics

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