Question

A book falls off a shelf that is 10.0 m tall. What is the velocity at which the book hits the ground?

Answer 1

Answer:

14 m/s

Explanation:

The motion of the book is a free fall motion, so it is an uniformly accelerated motion with constant acceleration g=9.8 m/s^2 towards the ground. Therefore we can find the final velocity by using the equation:

$v^2 = u^2 + 2gd$

where

u = 0 is the initial speed

g = 9.8 m/s^2 is the acceleration

d = 10.0 m is the distance covered by the book

Substituting data, we find

$v=\sqrt{0^2 + 2(9.8 m/s^2)(10.0 m)}=14 m/s$