A person jog eight complete laps around a 400 m track in a total time of 14.9 min. Calculate the average speed in m/s and average velocity in m/s?

The average speed of the person jogging is .45 m/s. This answer can be determined by taking 400m and dividing by 14.9 min. This will give you 26.8 m/min. You then convert the minutes to seconds in the denominator by multiplying 26.8 m/min by 1min/60s and you get .45 m/s.

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skyluke89 skyluke89 · Answer 2 · 2018-07-18T06:16:57-04:00

1) Average speed

First of all, we need to convert the total time from minutes to seconds. Keeping in mind that 1 min = 60 s, we have

[tex] t=14.9 min \cdot 60 s/min =894 s [/tex]

Each lap is 400 m, and the person completes 8 laps, so the total distance covered by the person is

[tex] S=8 \cdot 400 m=3200 m [/tex]

The average speed is just the ratio between the total distance and the total time:

[tex] v=\frac{S}{t}=\frac{3200 m}{894 s}=3.6 m/s [/tex]

2) Average velocity

The average velocity is equal to the ratio between the total displacement of the person and the total time:

[tex] v=\frac{d}{t} [/tex]

however, the total displacement is zero, because the person returns to his starting point (the track is a closed circuit). Therefore, d=0 and the average velocity is zero as well:

[tex] v=0 [/tex]