Question

an athlete completes one round of a circular track of diameter 200 metre in 20 second what is the distance covered and the displacement at the end of 2 minutes 20 seconds​

Answer 1

2min 20 sec=140 sec

diameter =200 ,radius =100m

1 round =20 sec.

then =140/20=7 round

displacement =0 (as body comes at its initial position after covering a distance )

• distance =2pi×r+2pi×r+2pi×r+2pi×r+2pi×r+2pi×r+2pi×r ( as one round of circle equals to 2pi×r)

Total =14pi×r (pi=22÷7)

Total distance =14×22/7×100=4400m