next up previous
Next: The Traction Circle Up: The Racing Line Previous: Aims of this

Motion on a Circle

In order to keep this section simple, we'll only try to do the calculations for objects on a turn of constant radius.

In order for a mass (M) to move around a circle of constant radius (r) it must be subject to a centripetal force of magnitude

acting perpendicular to the direction of motion (Tipler, p. 65).

This force is generated by the tyres, however, the total force that a tyre can generate is limited. The art of race driving is to balance the accelerating (braking) and cornering forces so that the total force stays within the `traction limit'.

Figure 8: The traction circle showing a car accelerating out of a right hand bend, close to the limit of traction.

Richard Bower
Thursday October 8 16:09:30 BST 1998