1. Velocity and Acceleration
Ch. 2 Pg

2. Objectives Relate motion of a freely falling body to motion with
constant acceleration
2. Calculate displacement, velocity, and time at various
points in motion of a freely falling object
3. Compare the motions of different objects in free fall.

3. Free Fall
In the absence of air resistance, all objects dropped near the surface of the Earth fall with the same constant acceleration.
Free fall acceleration (acceleration due to gravity)
g = 9.81 m/s2

4. at the top, the ball’s velocity and acceleration is zero
acceleration is slowing down (-)
direction is up (+)
g = m/s2
acceleration is speeding up (+)
direction is down (-)
g = m/s2

5. vf2 = vi2 + 2aΔy Free Fall Both Δx and Δy are displacement
Δx is horizontal displacement
Δy is vertical displacement

6. Example
Jason hits a volleyball so that it moves with an initial velocity of 6.0 m/s straight upward. If the ball starts from 2.0 m above the floor, how long will it be in the air before it strikes the floor? Assume that Jason is the last player to touch the ball before it hits the floor.