This week I spend designing and building my catapult to launch a golf ball 10 yards. During this project I learned that there are many factor that go into building a catapult. The biggest problem I had was getting enough tension in the springs to launch the projectile the full ten yards.
I ended up using 2 by 4 pieces of wood, rope, springs, and pvc pipe to build my catapult. I think my design and materials really provide a stable base and a strong enough arm to be able to support the golf ball.
I had to try several different positions of the spring to get enough tension in them so that the arm would have enough torque to launch the golfball the full 10 yards. The first place I placed the spring was on the bottom of the arm and the end of the base. This didn't work as well as I thought it would; the arm would come back but then either get stuck because the end would move off of the pvc pipe but even then the spring still did not have enough tension for the arm to have enough torque to launch the golf ball. I also tried adding another spring and crossed them over to see if that would keep the arm stable enough and add enough torque to launch the ball.
After all of those ideas failed I decided to move my placing of the springs to the top and created a V with the springs from the top of the base to the arm it self. This worked! It added enough tension on the arm because of how high I placed the end of the spring on the arm. This added enough tension to the springs to have enough torque to successfully launch the golf ball 10 yards.
Through this project I learned some important physics rules. I used Newtons second law during this project which states Acceleration is produced when a force acts on a mass; we saw the ball was accelerated forward when the force of the arm acted on its mass. I also learned that the more tension you have the more torque you create.