Projectile Motion
Linear Motion, Free Fall,
and Vectors Combined!
Projectile

Is any object that moves through air or
space acted on only by gravity (2
dimensional motion)
Projectiles

If a bullet is shot out of a gun horizontally
and another is dropped from the same
height, which will hit the ground first?
Why?
Components of Projectiles
(Vectors!)



Horizontal Component (x-direction): no
forces, constant velocity, no acceleration
Vxo = Vx
ax = 0
Components of Projectiles
(Vectors!)


Vertical Component ( y- direction) : force
of gravity, velocity changes, acceleration
ay = -9.80m/s2
Components are INDEPENDENT



The components do not depend on each other
Combined, they form the projectiles path (its
TRAJECTORY)
Time is the only factor that is the same in both
directions
Target Practice

If I were to shoot at a target, where
should I aim?
Components of a projectile’s velocity

For a vertically launched projectile, the
shape of the trajectory is a parabola:
Did you get it?



How do horizontal and vertical motion
effect each other in projectile motion?
Describe the velocity and acceleration in
the x direction.
Describe the velocity and acceleration in
the y direction.
Solving problems

Both horizontal and vertical motions are constant
acceleration so the old eq. of motion still apply!
x-component y- component

v= vo + at

d= do+vot+1/2 at2

v2=v2o + 2a(d-do)
Practice Problem

You decide to go cliff jumping and run off a 10.0 m
cliff with a horizontal velocity of 1.50 m/s. How far
from the bottom of the cliff will you land in the water?