Special Case: Constant Acceleration
For cases of constant acceleration, we can derive a set of "kinematic equations" that will allow us to solve for unknown quantities
Deriving the Kinematic Equations
Free Fall
When the only force acting on an object is the force of gravity, we refer to object's motion as free fall
This includes objects that have a non-zero initial velocity
Air Resistance
If we drop a ball and a sheet of paper, it is obvious they don't fall at the same rate
If we could remove all the air from the room, however, we would find that they fall at the same rate
We will analyze the motion of objects by neglecting air resistance (a form of friction) for the time being
Acceleration Due to Gravity
Near the surface of Earth, objects accelerate downward at a rate of 9.8m/s2
We call this acceleration the acceleration due to gravity (g)
More accurately, g is referred to as the gravitational field strength
As you move further away from Earth, g decreases