We studied the model for the height of a falling object that is [i]dropped[/i]. For an object that is [i]thrown[/i] down or up, the model has an extra term to take into account, the initial velocity. Problems involving these two models are called [i]vertical motion[/i] problems.

[b]OBJECT IS DROPPED[/b]: [math]h=-16t^2+s[/math][br][br][b]OBJECT IS THROWN[/b]: [math]h=-16t^2+vt+s[/math][br][br]  [i]h[/i] = height (feet)  [i]t[/i] = time in motion (seconds)[br][br]  [i]s[/i] = initial height (feet) [i]v[/i] = initial velocity (feet per second)[br][br]In these models the coefficient of [math]t^2[/math] is one half the acceleration due to gravity. On the surface of Earth, this acceleration is approximately 32 feet per second per second.

Remember that velocity [i]v[/i] can be positive (for an object moving up), negative (for object moving down), or zero (for an object that is not moving). Speed is the absolute value of velocity.