1. Catapult

2. What is a catapult?
A catapult is any kind of mechanical device that shoots or launches a projectile a great distance.
The word 'Catapult' comes from the two Greek words "kata" (downward) and "pultos" (a small circular battle shield).

3. refers to the motion of an object projected into the air at an angle
Projectile Motion
Projectile motion
refers to the motion of an object projected into the air at an angle

4. Projectiles In Motion

5. Projectiles In Motion

6. Catapult What are some key design goals when designing a catapult?
What angle will you use to shoot your projectile?
What will create a force to launch the projectile?

8. MATERIALS 3 - 20 cm long 6 - 10 cm long
cm long - the ends cut at 45o
cm - the ends cut at 45o
Small nails
1 metal bar cm long
1 large rubber band
2 eye hooks
Glue
Gussets-made of balsa
1 metal cup for basket

9. Constructing the Side Support
Using the 10 cm long pieces create 2 side supports that are mirror images of each other
Use both glue and nails to create the sides.
Add gussets for added strength

10. Now connect the two sides of the catapult together using the remaining four 10cm pieces. Use nails and glue
Note: The upright wood pieces (the two vertical ones) are on the inside of the catapult base.
Don't build it with these on the outside.
It is stronger this way!

11. Swing Arm Assembly
Drill a hole in the catapult arm about 2 cm from one end. This hole should just be a little bit bigger than the metal bar you are using.
Now put a hook about 7.5 cm from the other end of the arm.
Glue your metal cup to just above the hook

12. Add Catapult Arm to support
Slide the bar through the side support then through the catapult arm then into the other side support.
Add a bit of glue to bar and where it meets the side support to hold it firm

13. Add Elastic to Arm Put the other hook on the front of the catapult.
The arrow shows where to put it.
Then run a rubber band from that hook to the hook on the catapult arm.
NOW IT’S READY TO FIRE - GET SOME MINI BLOCKS AND FIRE AWAY!