Posted by Jesse on .
Omar throws a rock down with speed 12 m/s from the top of a tower. The rock hits the ground after 2.0 s. What is the height of the tower? (air resistance is negligible)

Physics 
bobpursley,
hf=hi+vi*t+1/2 g t
hf=0, Vi=12, g= 9.8m/s^2 solve for t.