Question

A sprinter is running toward the finish line at 7 m/s. When he is 12 m away from the finish line, he begins to fatigue and slows at a rate of -0.6 m/s^2 . How fast is he running when he crosses the goal line? *Round your answer to the nearest hundredth.

Answer 1

5.88 m/s

Step-by-step explanation:

The following data were obtained from the question:

Initial velocity (u) = 7 m/s

Acceleration (a) = –0.6 m/s²

Distance (s) = 12 m

Final velocity (v) =.?

We, can determine how fast the sprinter is running when he crosses the goal line as follow:

v² = u² + 2as

v² = 7² + (2 × –0.6 × 12)

v² = 49 + (–14.4)

v² = 49 – 14.4

v² = 34.6

Take the square root of both side

v = √34.6

v = 5.88 m/s

Therefore, the sprinter is running at a speed of 5.88 m/s when he crosses the goal line.