# 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/s

^{2}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