The projectile motion equation is s(t)=-16t^2+vt+h where s(t)
represents the distance or height of an object at time t, v
represents the initial speed of the object in ft/s, and h is the
initial height of the object, measured in feet.
If an object is starting at rest, then v=0 (such as for a penny
being dropped from a building). If the object is starting from the
ground, h=0. The baseball or cannonball situations, each have an
initial velocity. For...