Fire Away!

Proof of Efficacy of Catapult Modifications

Process Of Making Our Trebuchet

Our catapult has a metal arm, and a metal axle. We purposely did this so that there would be the least amount of friction possible. Our rubber band holder was a metal pipe that went through the wooden legs. We chose a metal pipe because it held our rubber bands sturdy, and it was the best placement to have maximum potential energy in our rubber bands. We used wood for our legs and base because they were easy to put together with screws, and they are a sturdy material that can withstand the pull back and release of the arm. We put a notch in the effort side of our arm so that the rubber bands would have a place to sit so that they wouldn’t fall off. We used nine rubber bands so that we could have the most amount of potential energy possible. The more rubber bands you have, the more potential energy there will be. However, you can’t have too many rubber bands, or else you won’t be able to pull your arm back far enough to get any potential energy. That is why nine rubber bands is the perfect amount. You can pull back your arm really far, and each rubber band will add more potential energy. Our arm developed a curve. We think this happened because of how much force the arm had when it connected with the base to stop it. The angle the arm has was actually beneficial to the catapult. This is so because, when we pulled back the arm, the extra curve upward caused more tension in the rubber bands, which produced more potential energy.

This project was connected with the Alternative Energy Vehicle project. So I linked this page to the Alternative Energy Vehicle page. There you can also find my reflection.