Song: "One Thing" by One Direction ©2011. Disclaimer* we do not own or claim to represent One Direction. All copyrights reserved.
For example, on the final day, with all of its bad weather, we launched three times. The first launch that day used 500mL of water and 40psi, and had a time of 5.3s. The second launch that day used 750mL of water and 55psi, and also had a time of 5.3s (I think that's what Mr. Blake said, so please pardon me if I am incorrect). The (unfortunate) final launch that day used 800mL and 60psi, and had a time of 7 sec. This is a great comparison to our first launch day— we used 500mL of water, 40psi, and no modifications to get 3 seconds in clear conditions. Although the first launch and the final launch's times were just a few seconds apart, the differences came from the weather conditions, the modifications, and especially the amount of water and pressure.
We learned so much that final day— the more water (fuel) and pressure, the better chance our rocket had staying in the air for a longer period of time. The relationship between those two variables was finally made clear as we realized that the more water, the longer the time, but more pressure was also needed in order to expel that fuel and propel the rocket.
Science was also an integral part of the various factors involved in this project. Amount of water, pressure per square inch, wind, weather, trajectory angle, mass, length, friction, and force were all closely examined and manipulated as needed. (A great site that helped explain this to me: http://microgravity.grc.nasa.gov/education/rocket/rktstab.html.) We found that the theoretical ideal conditions to make a water bottle rocket that lasted at least ten seconds were:
• a sunny, relatively calm day with a slight breeze (could help the rocket's time)
• 700-800mL of water and at least 60~psi to compensate for the amount of water
• a vertical trajectory angle (so the rocket would not get eaten by Konia's roof, Akahi's roof, or Midkiff's roof/tree)
• a 2-bottle, 2L rocket with four fins placed lower on the sides for the center of pressure
• a parachute made of a large trash bag, reinforced with duct tape and 8 strings
• a smaller nose cone that was able to easily pop off and deploy the parachute
Attempting to control all of these variables was quite exhausting and often beyond our reach. We did, however, have a lot of it explained from this website: http://www.ohio4h.org/sciencealive/rocketsaway.html) We did manage to create a pretty decent rocket, but our largest problem by far (besides the weather) was the nose cone, which did not always pop off and allow the parachute (which worked fine) to deploy. If our rocket had not gotten stuck in a tree, I would have liked to make an even smaller nose cone that may have worked better than the larger one.
Overall, we think we did a pretty good job at "building a better rocket." Our first rocket was basically a 2L bottle with fins and duct tape— nothing fancy. Our final rocket was a combination of 2 2L bottles, reinforced cardboard fins and duct tape, a large, circular trash-bag parachute reinforced with duct tape and 8 24in strings, a plastic nose soccer cone trimmed down with 2 v-shaped cuts in order to hopefully allow the parachute to deploy, and of course, "Zayn 2.0" scrawled proudly on a fin (referring to Keana's favorite band member of One Direction.)
This project is definitely recommended to future physics classes, as I am sure they will not only find it amusing, but also helpful in reinforcing their knowledge of physics. :)
