I've just come across a WP article which says: "The Jamaican sprinter Usain Bolt produced a maximum of 3.5 hp (2.6 kW) 0.89 seconds into his 9.58 second 100-metre (109.4 yd) dash"
Out of curiosity, I decided to figure out the math behind this. While doing so I found this very detailed paper exactly showing how this was all calculated.
The paper states that the effective work Bolt has put into motion was 6.36 kJ and that the peak power was 2619.5 W for a very brief period in the first second of the sprint. The paper also mentions that Bolt average horizontal force during the sprint was 815.7 N which makes the total work done during the 100 meters race equal to 81.58 kJ. The paper concludes that "This means that from the total energy that Bolt develops, only 7.79% is used to achieve the motion, while 92.21% is absorbed by the drag; that is, 75.22 kJ are dissipated by the drag, which is an incredible amount of lost energy"
Now if we take the figure of 81.58 kJ exerted in 9.58 s, that would give us ~8500 W of average power during the sprint which is a little bit more than 11 hp. So my question now is: can we safely say that Bolt average power during the 9.58 s sprint was 11 hp?
In other words, would an 11 hp engine say in a motorcycle of similar physical characteristics (total mass, drag coefficient..etc) to those of Bolt achieve the same 100 meters in 9.58 s?
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