an athlete completes one round of circular track of diameter 200m in 40 seconds what will be the distance covered and the displacement at the end of 2 minutes 20 seconds ?
Answers
Answer:
2pier=200
44/7r=200
44r=1400
r=1400/44
An athlete completes one round of a circular track of diameter 200m in 40s.
Given that, the diameter is 200 m. So, the radius is 100 m (half of diameter).
As the athlete covers the path in a circular motion. So, the displacement is zero.
Distance cover in one round (during 40 seconds) = 2πr
(2πr = Circumference of the circle)
→ 2 × 22/7 × 100
→ 4400/7
→ 628.571 m
Distance covered in 1 second (during first or one round) = 628.571/40 = 15.714 m
We have to find the distance covered and the displacement at the end of 2min 20s.
Displacement is zero (as the path is circular). But the athele covers 3.5 rounds (140/40). So, the displacement of the athele is equal to it's diameter of circle i.e. 200 m.
Distance covered in 2min 20sec or 140 sec = 15.714 × 140 = 2199.96 = 2200 m (approx.)