This article suggests a model for many road accidents, namely, those in which a vehicle being driven forwards encounters an obstacle such as a pedestrian, a vehicle, or a tree. An equation for speed of impact is obtained from the model. (Speed of impact is very important in determining severity of injury.) The equation is an expression in five variables. As it is elementary, it will be of interest to educators in mathematics and other subjects, as well as to road safety specialists. Two of the five variables (speed of vehicle, and distance of the obstacle) are conditions existing at the initiation of the emergency; and three are approximately termed: range of the sensing system; reaction time; and deceleration; and are properties of the system of driver and vehicle. Thus the focus is on the moment the emergency is appreciated, a few seconds before impact. The model and equation may be relevant to some railway accidents, also. In addition, the article discusses how to push our understanding to a point some seconds earlier, in the hope of throwing light on accident causation.
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D. F. Moore. Minimization of occupant injury by optimum front-end design. Society of...

An elementary expression in five variables relevant to many road accidents

10.21914/anziamj.v63.17113