SCIENCE JOURNAL 2018

statistics, the results seen become clear. Due to higher kinetic energy seen in faster moving ve- hicles, the ability for more energy to be trans- ferred onto other objects is increased – high- speed collisions > fender bender (Trefil/Hazen, 2010). Appendix One shows this, whereby the results show a correlation between speed and percentage of fatality. 2015 saw a fatality per- centage of 8.8% between the speed limits of 0-50km/h. In comparison, collisions at speed limits of 100-110km/h saw a 44.6% (near half) fatality percentage in which represents a dra- matic increase. With an increase of c.507%, these statistics highlight how increased speeds cause fatalities from a squared exponential in- crease in kinetic energy – more energy to trans- fer onto other objects. Moreover, these statistics are supported in Ap- pendix Six whereby the relationship between the degree of crash for both 50km/h and 100km/h promote the kinetic energy relationship dis- cussed. The percentage of fatalities to total crashes for both 50km/h and 100km/h are calcu- lated in Appendix Three. These percentages show how the likelihood of a more damaging accident to occur is greater at 100km/h (5.09% fatal) when opposed to acci- dents at 50km/h (0.87% fatal). From the infor- mation analysed in both appendixes, the conclu- sion can be made that increased kinetic energy at higher speeds result in more damaging colli- sions. Reaction and Braking Distance In addition to the exertion of kinetic energy, a person’s reaction time can significantly affect the speed in which a collision is experienced. The outcome of an accident can be improved through reacting to the hazard and braking. However, with increased speeds the distance in travelled in the same reaction time is greater. Thus, the braking distance (45m before object)

has diminished. Appendix Four calculates the approximate reaction time used for results illus- trated in Appendix Two. Using this approximate reaction time, Appendix Two shows this trend. At 50km/h, the reaction distance is c.21m, in which provides sufficient distance for braking to bring a vehicle to a complete stop (0km/h). However, reaction distance increases at a linear rate, with an additional 2m for every 5km/h in- crease in speed. Because of this, reaction dis- tance at 80km/h is c.13m greater (34m total) than that at 50km/h. As stated, diminishing re- turns are seen with braking distance decreasing, and at 80km/h, well past the distance needed to stop (colliding with object at 66km/h). Moreover, braking distance increases at higher speeds, seeing greater velocity on collision. Ap- pendix Two shows this trend, whereby incre- mental increases in speed by 5km/h sees a cubed exponential trend in braking distance, due to higher kinetic energy. At 50km/h, braking dis- tance is 14m, while at 80km/h braking distance is c.35m. This 30km/h increase in speed sees braking distance more than double. When ac- counting for both reaction and braking distance, the likelihood of a fatal collision dramatically upsurges at higher speeds due to impact velocity being greater (e.g. 66km/h when travelling 80km/h). As can be seen, the physical concepts leading to the claim show how higher speeds ultimately correlate to more damaging accidents – an out- come caused by speeding. Factors Environmental Factors and Friction Concept When applying the claim into a real-world sce- nario, certain factors begin to influence the abil- ity of physics to address the issue of speed re- lated accidents – in particular environmental factors. Factors such as weather conditions and road surfaces influence an outcome of speeding.

SC J SI

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Somerset College Journal of Scientific Issues

Year 10