science
posted by jo .
two tall buildings are 200m apart .with what speed must a ball be thrown horizontally from the window 540 m above the ground in one building, so that it will enter a window 50m above the ground in the other?

vertical problem
how long to fall 490 meters?
490 = (1/2)(9.81) t^2 solve for t
horizontal problem, same t
u t = 200
u = 200/t 
Using Range = u^2*2h/g (using g = 9.8m/s^2)
u^2 = r*g/2h
u^2 = 400
u=20m/s