Gravity and One-Dimensional Motion

One-Dimensional Motion Involving Gravity

The best way to see the basic features of motion involving gravity is to start with the simplest situations and then progress toward more complex ones. So we start by considering straight up and down motion with no air resistance or friction.

These assumptions mean that the velocity (if there is any) is vertical. If the object is dropped, we know the initial velocity is zero. Once the object has left contact with whatever held or threw it, the object is in free-fall. Under these circumstances, the motion is one-dimensional and has constant acceleration of magnitude \(g.\) We will also represent vertical displacement with the symbol \(y\) and use \(x\) for horizontal displacement.

Kinematic Equations for Objects in Free Fall Where Acceleration = −g