Question

A baseball dropped from the roof of a 47 meter building. How long would an object take to free-fall of the top of the building? [Neglect friction.]

4.8 s
4.8 s

2.1 s
2.1 s

9.6 s
9.6 s

3.1 s

Answer 1

Answer:

t = 3.1 seconds

Explanation:

Given that,

A baseball dropped from the roof of a 47 meter building.

Let t is the time taken by the baseball to free-fall of the top of the building. It can be calculated using second equation of motion as follows :

$s=ut+\dfrac{1}{2}at^2$

Here, u = 0 and a = g

$s=\dfrac{1}{2}gt^2\\\\t=\sqrt{\dfrac{2s}{g}} \\\\t=\sqrt{\dfrac{2\times 47}{9.8}} \\\\t=3.09\ s$

or

t = 3.1 s

So, it will take 3.1 seconds to free-fall of the top of the building.