A sprinter can accelerate with constant acceleration for 4.0s before reaching top speed. He can run the 100-meter dash in 10s. What is his speed as he crosses the finish line?(adsbygoogle = window.adsbygoogle || []).push({});

I need help with this problem.

I know that for the last 6 seconds because he has reached top speed that he has constant velocity. During the first 4 seconds I must use a Uniformed Accelerated Motion formula, and I think I need to actually combine 2 of them together; however, I get an unrealistic answer, like 15m/s, which I know is incorrect.

Please help me find the sprinter's speed as he crosses the finish line?

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# Homework Help: 100 Meter Dash

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