Fast-Moving Vehicles

A large fast moving truck moving past a small fast sports car
Credit: National Air and Space Museum, Smithsonian Institution

The sideward tug you feel on your car when you pass a large truck going in the opposite direction is caused by air pressure. The passing vehicles form a constriction that speeds up the flow of air, reducing the air pressure between them. The higher air pressure on the other side of the car pushes it toward the truck during the split-second as they pass.

Categories: Aerodynamics