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A boy runs in a 125-m race from rest. In the first 5 seconds, he increases his speed with a constant

acceleration of 2.0 m/s2. He then maintains this speed for the rest of the run. Calculate the total
time taken for the boy to finish the run.

1 Answer

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Answer:

Assuming starting at zero velocity: at 4 seconds speed is 8 m/s (2m/s^2 * 4 seconds) and distance is 16 m (average speed is 4 m/s * 4 seconds). The remaining 84 meters (at 8 m/s) takes 10.5 seconds.

So total time to run 100 meters is 14.5 seconds.

Step-by-step explanation:

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