1. Projectile Motion Everyday applications Vector additions
Some basic concepts
Practice, Practice, Practice

2. We see examples of projectile motion every day
Basketball: taking a jump shot
Golf: Driving off a tee
Football: QB throwing a BOMB
Can you think of others?

3. Projectile Motion The trajectory (curved path) a projectile
follows is always a combination of two
INDEPENDENT motions……
one vertical (affected by gravity) and
one horizontal (constant velocity)
Vertical motion: Horizontal Motion
Vf = Vi + at Vh = d/t
Vf2 =Vi2 + 2ad
d = Vit + 1/2at2
Projectile Motion

4. Projectile Motion When we are looking at an object that
Exhibits projectile motion, we MUST
Separate the motion into its’ VERTICAL
and HORIZONTAL components.
The vertical component is affected by
GRAVITY. It slows down on the way up,
and speeds up on the way down at a rate
of –9.81 m/s2. It is just like throwing a ball
straight up in the air.
Projectile Motion

5. Projectile Motion The HORIZONTAL component is NOT affected
by gravity, therefore, if we neglect air
resistance, the object should be moving
Horizontally at constant velocity (which means
NO Acceleration).
The equation we use for this is:
Vh = d/t
Projectile Motion

6. We will use Trig to find the components.
Sin q = Vv / 25.5 m/s
cos q = Vh / 25.5 m/s
25.5 m/s Vv q Vh
Use Trig functions to separate the vertical and
horizontal components of the trajectory. Then
use Vv and Vh to calculate the rest.

7. Projectile Motion Ready to try an example:
Let’s say we fire a cannonball with an initial velocity of 42.8 an angle of 37.3o with respect to the ground.
How long will the cannonball be in the air?
How high will the cannonball go?
How far away will the cannonball hit the ground?

8. Projectile Motion Draw a picture
Find your Vertical and Horizontal components
+ and – are very important for vertical motions
Solve vertical motions first
Last solve horizontal motions.

9. Projectile Motion
As long as you are careful in taking apart these types of problems, and ask the right questions, they are solved easily. There is just a lot of math. Remember : Sig Figs COUNT!
Now Let’s try another one: