A person walks along an east-west street and a graph of his displacement from home is shown in figure. His average velocity for the whole time interval is:-

Options

A. 8 m `min^(-1)`
B. 5 m `min^(-1)`
C. `(8)/(3)` m `min^(-1)`
D. 2 m `min^(-1)`

Answer

B

Explanation

Distance from 0 to 5s = 40 m
Distance from 5 50 10s = 0 m
Distance from 10 to 15s = 40 m
Distance from 15 to 20s = 20m
So, net distance = 40 + 0 + 40 + 20 = 100 m
Total time taken = 20 min.
Hence, average speed
` = ("distance(m)")/("time(min)") = (100)/(20) = 5 m min^(-1)`