Circular Motion Interactive: Exploring Centripetal Force on Flat and Banked Tracks

There is no centripetal force

Centripetal force is a role, not a thing. Whatever real force points at the centre fills that role — friction on a flat road, a component of the normal force on a banked track. Drag the slider below to increase speed and watch friction change colour as it tries (or fails) to keep the car on the curve.

Flat Circular Road Speed: 15 m/s

Friction provides the centripetal force — up to a limit

Static friction available
0 10 20 30 40
Req'd Force 562 N
Friction Limit 2400 N

On a flat circular road, static friction between the tyres and road provides the centripetal force. The maximum static friction sets the maximum safe speed. Once you exceed that limit, friction can't pull hard enough toward the centre — the car slides outward. This is why sharp corners have lower speed limits: the tighter the radius, the more force required to keep turning, and friction can only provide so much.

Know This

Centripetal force is a role, not a new force — friction, tension, gravity or the normal force fill it, and a = v²/r always points toward the centre of the circle.