A sprinter accelerates to his max speed in 4.0s. He then maintains this speed for the remainder of a 100-m race, finishing with a total time of 9.1s. What is the runner's avg acceleration during the first 4.0s, during the last 5.1s?(adsbygoogle = window.adsbygoogle || []).push({});

I know that the runner starts at 0-m for his initial position and his final position is 100m. I also know that the acceleration from 4.0s-9.0s is 0 because he keeps the same speed. It seems I still have 2 unknown variables when trying to find the position after 4.0s and velocity for each part of the race.

100m=X + V(5.1s) Have 2 unknowns here

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# Homework Help: Speed and Acceleration Question

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