Calculating Building Height Using Balloon Drop Experiment

[delfam]

Homework Statement

you and your friend throw balloons filled with water of a roof of a building. You drop yours from rest, he throws his with an initial speed of 72.52 m/s^2 3.7 seconds later. They hit at the same time. How high his the building.

Homework Equations

V=Vi+at
(V^2) - (Vi^2)/(2a)= deltax

The Attempt at a Solution

V=72.52 = 9.81(3.7), V = 108.78
(108.78)^2 - (72.52)^2/(2)(9.81) = deltax
deltax = 334.73 m

 

[TxRationalist]

seems to me that you have to set up two equations, one for the v0 = 0 at time T and one for v0 = 72.52 m/s at time = (T - 3.7). that's my take...I haven't tried plugging these in, though.