Drops of water fall at regular intervals from the roof of a building of height 16m, the first drop striking - Physics - Motion In A Straight Line

Question

Drops of water fall at regular intervals from the roof of a
building of height 16m, the first drop striking the ground at the
same moment as the fifth drop detaches itself from the roof Find
the distance between the separate drops in the air, as the first
drop reaches the ground

Himanshu · Accepted Answer

Let the time interval between the falling of two drops from the roof be t seconds. Therefore, according to the question a drop take 4t seconds to reach the ground from the top of the building.

$16 = \frac{1}{2} g (4 t)^{2} \Rightarrow t^{2} = 0.2 \Rightarrow t = \frac{1}{\sqrt{5}}$

$d_{2 n d d r o p} = \frac{1}{2} g (3 t)^{2} = 9 \frac{g t^{2}}{2} = 9 m d_{3 r d d r o p} = \frac{1}{2} g (2 t)^{2} = 4 \frac{g t^{2}}{2} = 4 m d_{4 t h d r o p} = \frac{1}{2} g (t^{2}) = \frac{g t^{2}}{2} = 1 m$

Drops of water fall at regular intervals from the roof of a building of height 16m, the first drop striking the ground at the same moment as the fifth drop detaches itself from the roof. Find the distance between the separate drops in the air, as the first drop reaches the ground.