A car overturns outward when turning at high speeds due to inertia, as described by Newton's law. Inertia causes objects in motion to maintain their straight-line path, leading the car to want to move outward from the curve. The friction between the tires and the road surface is the force that redirects the car, but because this force acts below the center of gravity, it creates an imbalance. If a barrier were positioned at the car's center of gravity height, it would prevent rolling. Unlike bicycles or motorcycles, which can tilt inward to counteract this outward tendency, cars cannot do so effectively due to their size and flat tires.