Question

I am looking out a window that is 1.3m tall. A water balloon suddenly drops across the entire length of the window in .22 seconds. How far above the window was it dropped?

Answer 1

average speed across window = 1.3/.22
= 5.91 m/s
speed at top of window = Vt
speed at bottom of window = Vb
in general
v = Vi + g t = Vi + 9.81 t
so
Vb = Vt + .22*9.81 = Vt + 2.16
Vt+Vb = 2 Vt + 2.16
(1/2)(Vt+Vb) = Vt + 1.08 = 5.91
so
Vt = 4.83 m/s
how far did it drop from a zero speed start to get to 4.83 m/s at the top of the window?
v = 0 + 9.81 t
4.83 = 9.81 t
t = .492 seconds
so
d =(1/2)(9.81)(.492)^2 = 1.19 meters