Step-by-step explanation:
It is given that,
Distance covered by the runner, d = 400 m
Time taken to complete one lap, t = 50 s
We need to find the magnitude of the average velocity of the runner. Total displacement divided by total time taken is called the average velocity of the runner. Here, the total displacement is 0 as runner come back to same point.
It is given by :
v = 0
So, the average velocity of the runner is 0. Hence, this is the required solution.