A cyclist moving on a circular track of radius `50 m` completes one revolution in `4` minutes. What is the (i) average speed (ii) average velocity in one full revolution ?

Explanation

Distance travelled in one revolution,
`= 2 pi r = 2 pi xx 50 m`
Displacement in one revolution `= 0`.
Time taken `= 4 "minute" = 4 xx 60 s`
`:. "Average speed" = ("distance")/("time")`
`= (2pi xx 50)/(4 xx 60) = (5pi)/(12) m//s`
`"Average velocity" = ("displacement")/("time") = zero`.