A stone is dropped from a height of 125 m. If g = 10 ms–2, what is the ratio of the distances traveled by it during the first and the last second of its motion?
1 : 9
Since the initial velocity of the stone is zero, the total time taken by the stone to hit the ground is given by
= 5 s
During the first second, the stone falls a distance h1 given by
During the first four seconds, the stone falls a distance h given by
Distance h2 through which the stone falls in the last (i.e. fifth) second
= 125 – 80
= 45 m.
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