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Question
Multiple choice Question. Select the correct option.
A body dropped from the top of a tower reaches the ground in 4s. Height of the tower is
Options
39.2 m
44.1 m
58.8 m
78.4 m
Solution
78.4 m
Explanation:
Initial velocity = u = 0
Time = t = 4s
As body falls downards,
so acceleration = a = + g = a = + 9.8 ms−2
(Distance) S = ut + 1/2 at
S = (0) (4) + 1/2 × 9.8 × (4)3
s = 0 + 1/2 × 9.8 × 16
S = 9.8 × 8 = 78.4 m
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