Class 10/2/08

Today was our first day back in class for about a week. After answering more D2L questions, we discussed projectile motion. Dr. E showed us a cannon simulation from the internet. We shot the cannon at a 90 degree angle, only to find that the cannon shot straight up and came back down due to the forces of gravity. Then we shot the cannon at a 75 degree angle. Its path was in the shape of a parabola (parabolic path). Dr. E explained that the virtical direction is by acceleration due to gravity. The horizontal direction of motion is constant. Next, we tested a 45 degree angle, only to find that this shoots the cannon ball the farthest distance in the x direction (horizontally). After the simulation, we made paper airplanes in order to find out which design had the longest hang time. Our group found that the flatter the airplane was, the longer the hang time. Our airplane was pretty flat, and it seemed to float in the air. Our other designs, that were not as flat, seemed to take a nose dive as soon as they took off. Overall, class today was a good learning experience, althought I did not understand the inverse square law we talked about at the begining of class.