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Velocity dispersions in a cluster of stars: How fast could Usain Bolt have run?

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 نشر من قبل Hans Kristian Eriksen
 تاريخ النشر 2008
  مجال البحث فيزياء
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Since that very memorable day at the Beijing 2008 Olympics, a big question on every sports commentators mind has been What would the 100 meter dash world record have been, had Usain Bolt not celebrated at the end of his race? Glen Mills, Bolts coach suggested at a recent press conference that the time could have been 9.52 seconds or better. We revisit this question by measuring Bolts position as a function of time using footage of the run, and then extrapolate into the last two seconds based on two different assumptions. First, we conservatively assume that Bolt could have maintained Richard Thompsons, the runner-up, acceleration during the end of the race. Second, based on the race development prior to the celebration, we assume that he could also have kept an acceleration of 0.5 m/s^2 higher than Thompson. In these two cases, we find that the new world record would have been 9.61 +/- 0.04 and 9.55 +/- 0.04 seconds, respectively, where the uncertainties denote 95% statistical errors.



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