You throw a ball downward from a window at a speed of 2.7 m/s. How fast will it be moving when it hits the sidewalk 2.9 m below?

Answer 1

s = 2.9 - 2.7t - 4.9t^2
s=0 when t=0.54s

v = -2.7 - 9.8t
v(.54) = -8m/s