Calculating speed and velocity

Question

A person jogs eight complete laps around a 400-m track in a total time of 14.5 min. Calculate (a) the average speed and (b) the average velocity, in m/s.

Answer 1

Average speed is defined as the total distance traveled divided by the time taken to travel. The person goes 400 meters 8 times, so their total distance is 8*400 = 3200 meters. We can convert the time to seconds by 14.5*60 = 870.

Dividing these gives us 3200/870 = 3.68 m/s

For average velocity, we need displacement divided by time. Displacement is the difference between the starting and ending positions. If the runner made 8 complete laps, then they stop exactly where they began. So, their displacement is zero. Thus, their average velocity is zero.