Question

An athlete completes one round of a circular track of diameter 200 m in 40 s. What will be the distance covered and also the displacement at the end of 2 min 20 s?

Answer 1

Total given time $=20min20sec=(120+20)sec=140sec$

Time period od revolution $=40sec$

Hence the no. of revolution complete in $140sec$

$n=\frac{140}{40}=\frac{7}{2}=3.5$

Distance cover $=3.5\pi d=3.5\times \frac{22}{7}\times 200=2200m$

Displacement cover is $=d=200m$

because at $3.5$ revolution athelete is at opposite to initial starting point.