Answer:
the height of the building will be 19.6 meters.
Explanation:
writing equation of motion in vertical direction:
[tex]s=ut-\frac{1}{2}gt^{2}[/tex]
where u is initial velocity of the object which is equal to 0
and g is the acceleration due to gravity g = 9.8m/[tex]s^{2}[/tex]
therefore the equation becomes
[tex]-h=-\frac{1}{2}gt^{2}[/tex]
h=[tex]\frac{1}{2}9.8\times 2^{2}[/tex]=19.6 meters