$\sf\underline\bold{Question:1-}$
A ball is thrown upwards and it goes to the height of 100meter and comes down. What is the net displacement?
$\sf\underline\bold{Solution}$
$\sf{According \: to\:the\: question,}$
Displacement for the above situation is 0. As we know, that displacement is the shortest path from the initial to the final point. Here, the initial and the final points are the same, and henceforth, it takes no time to travel. So the displacement is 0.
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$\sf\underline\bold{Question:2-}$
An athlete completes one round of a circular track of diameter 200m in 30 seconds. Find the distance covered by the athlete at the end of 30 second.
$\sf\underline\bold{Solution:}$
$\sf\bold{Given\:parameters:}$
$\sf\small{☆The\:diameter\:of\:the\:circular\:track:200m}$
$\sf{Radius=}$ $\sf\dfrac{200}{2}$ → $\sf\underline{Radius = 100m}$
☆Time taken by an athlete to complete one round : 30 seconds.
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$\sf\bold{To\:find:}$
❍Distance travelled by an athlete in 30 seconds.
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❍ AND,Distance travelled by the athlete will be equal to the cumference of the circle.
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$\space$ $\space$ $\space$ $\space$ $\space$ $\space$ $\sf{So,}$
$\mapsto$ $\sf{Circumference\:of\:the\:circle: 2 πr}$
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$\mapsto$ $\sf{Circumference=2\times}$ $\sf\dfrac{22}{7}$ $\sf{\times 100}$
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$\mapsto$ Circumference of the circle : $\sf\dfrac{4400}{7}$
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||Therefore,The distance travelled in 30 seconds, by the athlete is 628.57m.||
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