(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

On June 14th, 2005, Asafa Powell of Jamaica set a world's record for the 100-m dash with a time t=9.77s. Assuming he reached his maximum speed in 3.00s, and then maintained that speed until the finish, estimate his acceleration during the first 3.00s.

2. Relevant equations

v_{x}=v_{0x}+a_{x}t

x-x_{0}=v_{0x}t+^{1}/_{2}a_{x}t^{2}

v_{x}^{2}=v_{0x}^{2}+2a_{x}(x-x_{0})

3. The attempt at a solution

I broke the run into two segments, one of 3s with constant acceleration, and the other of 6.77s with 0 acceleration. The distance traveled in the first segment is 100m - the second, and the same is true of the second segment in relation to the first. Beyond that, I've been fumbling around with this problem for two hours and I'm still no closer to solving it than when I started.

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# Homework Help: 1D kinematics - 100m dash

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