Braking force of automobiles
Date: Around 1993
Does anyone know the average braking force of an automobile?
General rule of thumb: maximum longitudinal or transverse force
is about 1 g.
Actually that is quite accurate. It boils down to the
coefficient of friction between common tire rubber and the pavement which is
about 0.92 g (average) braking force and about 0.7 g after it is sliding. The
equations get a little more difficult though, when you take into consideration
the interlocking surfaces of the common soft-rubber tire and the rough surface
of most pavements. Width of the tire has no effect on smooth surface
coefficient of friction, but does have an effect on the interlocking surface
effects of the tire. In effect, the softer the rubber, and the rougher the
surface, the higher the braking force. For example, some Formula One cars
have braking forces that exceed 2.5 g's!
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Update: June 2012