Rolling Resistance vs. Aerodynamic Drag

Every kilometre a vehicle travels is paid for by two competing forces: rolling resistance at the tire contact patch, and aerodynamic drag pushing back on the whole car. This simulator renders a real 3D vehicle on a road you can resurface — asphalt, gravel or sand — with adjustable speed, mass and tire pressure, and computes both forces from their real physics formulas in real time. Watch the energy-budget bar flip from rolling-dominated to drag-dominated as speed climbs past the crossover point, and see why sustainable-transport engineering targets different levers at city speeds versus highway cruising.