We choose to do a catapult that is similar to the designs above because it is simple to make and easy to design. It does not use much PVC piping and it can fit easily into the 2X2X1.5 box.
The sketch for our catapult
Two 1 ½ foot pieces of pvc pipe, Six 1 foot pieces of pvc pipe, One 1 ¼ Feet of pvc pipe, Five T connectors, Seven Corners, Bungee Strap, 8 ¾ Feet of pvc pipe
What We Need To Buy: Four T connectors
Reflection: The first time we launched our catapult, we noticed that if we pulled the lever all the way back, then the ball will go straight up and hit the ceiling. We had to make a few changes so that the ball would not hit the ceiling and we decided to not pull the lever all the way back but to pull it with one inch from it touching the ground and this caused the ball to sail through the air rather than hit the ceiling.
Math Integration Documentation
Final Reflection Questions:
Our projectile hits the ground at 17 feet.
The maximum height of the ball is 8 feet and it occurred around 8.5 feet.
The height it is at when is traveled 6 feet is around 6 feet high.
By pulling the lever on our catapult back all the way would make the max height higher and that will change the vertex and height.
Vertex Form Trajectory Equation