What did we do?

We built a kicking machine to test different sized legs in a soccer kick. With a spring acting as the leg's "muscle," we added attachments that made the mass of the leg two and three times heavier. We tested each "leg" three times - the light leg, the medium leg and the heavy leg - to see how far it kicked the ball. Strangely enough, we found out the lightest leg kicked the ball farther every time. We found out that the heavy leg wasn't swinging as fast as the light leg. So, we added a second spring to give the heavier leg more speed. With one spring on the light leg, the ball flew an average of 47 feet. With one spring on the heavier leg, it only flew 27 feet. When we added the second spring, the heaviest leg sent the ball sailing to 55 feet! more...