An athlete complete one round of a circular track of radius R in 40 seconds. What will be his displacement at the end of 2 min 20 s?
The athlete completes one round of the circular track in 40 seconds.
Total time given = 2 minutes 20 seconds = 140 seconds
Number of rounds completed = 140 ÷ 40 = 3.5 rounds
Class 9th Science NCERT MCQ Questions
NCERT Books MCQ Questions Session 2024-2025.
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(b) As the athlete completes one round of a circular track in 40 s, hence in 2 min 20 s (or 140s) he will complete 7/2 rounds. Thus as shown in figure if he starts running from point A then on completion of 7/2 round he will be at point B. Thus, net displacement of the athlete AB = 2R.
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