Water Filter Project: In our last project we did in this class we had to filter water through filters we made in small groups. Our group was assigned the country of Kenya; Kenya's little water that they have is mainly contaminated with dirt, fecal matter and bacteria. We then tested our filter that we made out of easily accessible and or importable materials to our area.
Water Rocket Project
Rocket Construction: First, we took a 2 liter soda bottle and used that for our base. We decided to just use one solid container instead of attaching two cause when we first started and made it out of two there were a lot of leaks and other issues. Then we took the nozzle end of a separate bottle and attached it to the closed end of our rocket so it would be more aerodynamic. After this we put 4 fins along the middle of it in the shape of a triangle in order to give it stability.
Our testing variable was pressure, we chose this as our variable because it was something not everyone was doing. We felt it was the best measure due to the circumstances of all our different rockets. Also it was the easiest to keep the other parts of it constant so it was more exact and not as unreliable. We tested it with the pressures 70,80,85, and 100 and found that 85 worked the best out of the 4 different ones.
Our question: What PSI will make the rocket go the highest?
Our hypothesis: If pressure affects the height a bottle rocket projects into the air, then the higher the pressure the higher the rocket will go because with more pressure help in the bottle when released it will have greater momentum.
To test our rocket we started at 70 psi and increased each time by 10 and 5 each launching. We did four test launches. After each testing we would record the angle of elevation, the hang time, and height. At the end we compared our results to see which one had the greatest height that we could use to launch.
water - 750 ml
mass of rocket
distance from launcher - 10 meters
fin shape - thin, stiff, triangle shaped plastic
shape of rocket
aerodynamics- nozzle cone, streamline body and thin fins
the bottle launcher - used same launcher every test on flat stable ground
launcher nozzle - used same nozzle every test
We were not able to keep the following variables constant:
We collected data by recording the angle, hang time,distance and the pressure we used. We chose to display our data in a scatter plot graph because we felt that it represented how are rocket traveled due to our variable.
In conclusion, once testing multiple rockets that each had a different element to the rocket, we determined that the rocket performs the best when the pressure is right around the middle. Having the pressure to low caused the rocket to not have enough thrust to reach a high distance and to high of pressure causes the thrust to be too great in the beginning so it would become unbalanced. A difficulty that we came across was trying to keep our variables constant because we didn’t have a lot of time to do various amounts of testing and when we did we lost a couple of our rockets which then pushed back our time. Along with that we had to remake our rockets numerous amount of times due to them not being stable or other aspects such as having to change the fin then our variables became inconstant.