A runner hopes to complete the 10,000 m run in exactly 30 minutes. After exactly 27 minutes, there are still 1100 meters to go. The runner must accelerate at .20 m/s^2 for how many seconds in order to achieve the desired time? Assume the runner ran with constant velocity for the first 27 minutes.(adsbygoogle = window.adsbygoogle || []).push({});

Here's what I did:

8900 m/27 minutes

8900 m = .5(V0 + Vf)1620 s

Vo + Vf = 10.9 m/s

Vf= 5.5 m/s

1100 m = 5.5t + .5(.2 m/s^2)t^2

t= 80.9 seconds

Is this right?

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# Homework Help: A runner

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