brake efficiency meter

The braking efficiency of a car can be found simply by measuring the time taken to bring the car to a halt from a known velocity. The deceleration in feet per second 2 is then found from the equation: V a= -- t where v is the velocity in feet per second and t is the time, in seconds, taken to halt the car. This can be converted into `g` by dividing by the factor 32. On a sound road surface in dry conditions, a car with good brakes and tyres should be able to manage a deceleration in excess of 0.5 g.