1. By: Sam, Jacob, and Wendell
Projectile Motion
By: Sam, Jacob, and Wendell

2. Outline Drag (air resistance) How does air density affect trajectory
How does wind affect affect trajectory
Model of a cannon in 3 dimensions (java)

3. Recap • Shoot a projectile at a target • Time step is .01 seconds
• Optimal angle 45°

4. How drag works Drag = cd * r * V2/2 * A
Drag coefficient (cd) is a constant on earth
Density of the air ( r ) changes with altitude
Velocity of the cannon ball (V2) starts between 400 and 500 m/s
Surface area of the cannon ball (A) is m2

5. 3D plot Added Z axis Used two graphs to get 3D Wind in two directions
New angle (Z)
Y,X X,Z

6. Density change
Higher altitude less density No change in density

7. Wind
No wind on the Y axis
Wind factors into drag

8. No wind • + wind increases drag • no wind gives the
• - pushes the ball ball a natural path
a graph with no wind

9. Results Wind has little effect on trajectory of a cannon ball
Density change can make a cannon ball go farther
Adding the Z axis made it much harder to hit the target

10. References http://www.grc.nasa.gov/WWW/K-12/airplane/falling.html