A person sitting in the ground floor of a building notices through the window, of height 1 . 5 m , a ball dropped from the roof of the building crosses the window in 0 . 1 s . What is the velocity of the ball when it is at the topmost point of the window? g = 10 m s - 2

Question

Aicharya · Accepted Answer

First, recall the second equation of motion of kinematics, in terms of initial speed, time, and uniform acceleration, $s = u t + \frac{1}{2} a t^{2}$ . Now make a diagram related to motion of the particle,

then put the values in second equation of motion,

$\Rightarrow 1.5 = u (0.1) + \frac{1}{2} (10) (0.1) (0.1)$ $\Rightarrow 15 = u + 0.5$

$\Rightarrow u = 14.5 m s^{- 1}$ .

A person sitting in the ground floor of a building notices through the window, of height 1 . 5 m , a ball…

Solution