Final answer:
The question involves the concept of speed, distance, and time in physics. Given a speed of 5 m/s and a distance of 400 m, using the equation time = distance/speed gives us a calculation of 80 seconds for the athlete to complete one lap.
Step-by-step explanation:
This is a question of basic physics, specifically relating to the concept of speed, distance, and time. These three elements are connected by the equation speed = distance/time. In this case, we know the speed (5 m/s) and the distance (400 m), so we can rearrange the equation to solve for time. This gives us time = distance/speed.
Substituting our known values into the new equation, so that's time = 400 m / 5 m/s, which simplifies to 80 seconds. Therefore, it takes the athlete 80 seconds to complete one lap around the track at a constant speed of 5 m/s.
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