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प्रश्न
A stone is dropped freely from the top of a tower and it reaches the ground in 4 s. Taking g = 10m s-2, calculate the height of the tower.
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उत्तर
Initial velocity u = 0
Time t = 4 s
g = 10 m/s2
Let 'H' be the height of the tower.
Using the second equation of motion,
H = ut + (1/2) gt2
Or, H = 0 + (1/2)(10)(4)2
Or, H = 80 m
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