Sample Lab Writeup
eighth grade

C.T.
8th
3/8/01
assignment #32

For the chapter we were studying, my teacher decided to make us do an experiment on just how far a small projectile would fly, at any given angle. This having been announced, we marched on down to the cafeteria and set up our catapult and commenced firing. We quickly found that many things could effect how far a small projectile could fly. I will try to explain in the clearest way possible just how we decided to test question.

After talking with my parter, ---- ------, for quite some time, we concluded that we thought that 50 or 40 degrees would be the best angle to have the greatest impact on the small projectile. We believed this because we knew that at 10 degrees most of the force acting on the ball would be directed vertically rather than horizontally causing the ball to fly up into the air and not as far as would be wished, however, at 90 degrees most of the force acting on the ball would be directed horizontally rather than vertically causing the ball to drop quicker and not fly as far.

To complete this experiment we used a wooden block connected with tape to a plastic spoon. After that we taped a large puffball to the bottom of the lip of the spoon. We then held the block at the correct angle that was being tested in that instant and put a large puffball in the center of the lip of the spoon. We then commenced firing. After firing we measured in centimeters how far the projectile had flown from the starting point to the ending point. We fired the puffball twice at any given angle.

In this experiment we could have encountered any nuymber of problems, I will attempt to list but a few of them. First of all, we might have pulled the spoon back further for any given angle than another. Secondly, we might have ot been able to hold the block and spoon in the exact angle desired. Thirdly, the tape around the steadying puffball might have caught the projectile. Fourthly, some people might have let the projectile roll and then measured it.

We observed that the lower degrees (10-30) Flew too high to go very far, however the higher degrees (60-90) went further than the middle degrees (40-50). In fact, 90 degrees went the farthest with some rolls. I was also not able to measure exactly the length of the flying projectile's path as sometimes some passerby kicked it. I think that 40-50 degrees would have sent the projectile the furthest had we not measured the rolls of the puffball.

We concluded that at 90 degrees the projectile would go furthest based on the limited information we were forced to gather. Since humans are prone to failure, 90 degrees cannot be at all accurate if you wanted to get technical on this assignment. Also, if we had better tools than a wooden block and plastic spoon, the projectile would have gone further. Furthermore, puffballs are not the best things in the world to use as a projectile. Thank you.