I'm new to this place so I really didn't know where to post this but here's the deal. My Physics teacher assigned us a projectile related to projectile motion. We are to build a siege weapon (catapult, trebuchet, ballista, etc.) that would launch a 1lb water balloon 25 ft in distance. We are planning to build a ballista and we know that to get the furthest distance, the ballista must be angled at 45 degree. However, I am having trouble understanding how the tension stuff works to calculate how much is needed to send the water balloon flying far enough to get a 100 on the project. Can someone please help me?