g = 9.8 m s-2
time (t) = 2.5 s
Initial velocity (u) = 0
h = ut + 1/2 × gt2
= 0 × 2.5 + 1/2 × 9.8 × 2.52
= 0 + 4.9 × 6.25 = 30.6 m
Hence, the height of the building is 30.6 m
Question
A body falls from the top of a building and reaches the ground 2.5 s later. How high is the building ? (Take g = 9.8 m s-2)
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