Kinematics Equation Help: Calculating Runner's Acceleration for 10,000m Run

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To determine how long the runner must accelerate to finish the 10,000m run in under 30 minutes, the runner has 1100m left after 27 minutes. They need to reach a speed of 6.1 m/s to complete the race on time, requiring an acceleration of 0.20 m/s². The discussion suggests using the SUVAT equations, particularly the formula d = vit + 0.5at², to calculate the time needed for acceleration. The calculations indicate that the runner will need to accelerate for about 3 seconds. Proper application of these equations will clarify the solution.
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A runner hopes to complete the 10,000m run in less than 30.0 minutes. After exactly 27.0 minutes, there are still 1100m to go. The runner must then accelerate at 0.20m/s^2 for how many seconds in order to achieve the desired time.


I have calculated the runner moving at 5.5m/s^2 for the first 27 minutes. I have no idea how to calculate this problem, all I know is that it will need to be divided into two parts.


With 180 seconds remaining, the runner would need to be going 6.1m/s^2 to complete the race on time. So they will need to accelerate about .6m/s^2 which is about 3 seconds, but I don't know what equations I need to plug into one another to show my work for this problem.
 
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NRasmus1 said:
A runner hopes to complete the 10,000m run in less than 30.0 minutes. After exactly 27.0 minutes, there are still 1100m to go. The runner must then accelerate at 0.20m/s^2 for how many seconds in order to achieve the desired time.


I have calculated the runner moving at 5.5m/s^2 for the first 27 minutes. I have no idea how to calculate this problem, all I know is that it will need to be divided into two parts.


With 180 seconds remaining, the runner would need to be going 6.1m/s^2 to complete the race on time. So they will need to accelerate about .6m/s^2 which is about 3 seconds, but I don't know what equations I need to plug into one another to show my work for this problem.

It's 5.5 m/s
You have initial velocity, acceleration and and distance. Use SUVAT formula to solve the time taken.
 
I think you must use d=vit+0.5at^2 or a variation of that.
 
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