Question

an athlete completes one round of a circular track of 200 metres in 40 seconds what will be the distance covered and the displacement at the end of 3 minutes 20 seconds

Answer 1

Given : Diameter of circular track = 200 m

Radius 'r' = 200/2 = 100 m

Time taken by the athlete to complete one round of circular track = 40 seconds

Now, time = 2 min 20s = (2 × 60) + 20 = 140 seconds            (Since, 1 minute = 60 seconds)

Number of rounds covered by the athlete = Total time / Time taken to complete one round

= 140/40 = 3.5

Circumference of a circle = 2πr

Distance covered in 1 round = Circumference of the circular track

Thus, the circumference of the circular track = 2 × 22/7 × 100

Distance traveled in 140 seconds = Number of rounds covered × Circumference of the track

= 3.5 × 2 × 22/7 × 100

= 0.5 × 2 × 22 × 100

Thus, the distance covered by the athlete is = 2200 m

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