9+Physics

=Physics Design Challenge Report= __Day One__: We spent time just testing how the bottle would shoot off of the launcher, and testing the pump and device to shoot up the bottle. We had many failed attempts, but then got the rocket to shoot up high. We know that the bottle rocket will shoot up properly. We used mass in this design by filling the bottle with air and water. The mass of the bottle changes as water is expelled and the rocket flies upwards. Inertia is a force used in this experiment as well. Without inertia, the rocket would not stay in motion after being shot up. Weight is another important factor, we had to ensure that the bottle was not too light and not too heavy so that it could shoot up to optimum height. Gravity is a force that is actually working all the time, and pulls the rocket down after launch, but with enough power, the rocket will stay in motion for longer. __Day Two:__ Today we attached the wings on our rockets using manila folder doubled over for strength. Using hot glue guns, we secured three at every one-third part of the bottle body. We used clear duct tape to cover the wings because we found that water sprayed them. The wings will hopefully allow the bottle to travel faster and higher because the wings will break the air resistance pushing on the bottle as it travels upwards. We tested this and it seems to work, but we cannot get the pump to work correctly… hmm.. Okay we tested it. Regan put her wings on the incorrect way, reverse to ours, which caused her rocket to shoot to a lower height. __Day Four:__ Today we created the cone on the top of the rocket because we realized that the parachute and the bottle bottom have too large of a surface area and do not efficiently break the surface area. To do this, we used plastic clear folder rolled up into a cone and glued with a hot glue gun. We did a test launch with the parachute stuffed into the cone but the cone did not fall off easily enough, so we tried again loosely placing the cone atop the crinkled parachute. This was a success. After hitting optimum height, the cone fell off of the rocket and the parachute caught the air, and the large surface area allowed it to fall down slowly. __Day Five:__ Today, when test launching the rocket, we found that the nozzle of the pressure pump was attached to a tube that pumped the air. We had two problems with getting the rocket to launch. One: The rocket nozzle was still attached to the pump after pulling the white tab that kept the closed together. Two: The rocket would try to shoot off, and would fall to the side with the pump still attached, and then shoot off sideways, parallel to the ground instead of upwards. In order to fix this, we did two things. First: we added grease to the nozzle in order to allow for a smoother launch. Second: we added straws on two sides of the bottle, which we slid onto two metal rods that were put into the ground. This was like a launch pad, to guide the rocket into straight up paths. __Day Six:__ All is well now, the launch problems are fixed, the parachutes (which broke last time due to rough handling) are fixed and working, and we managed to complete the challenge and meet the criteria of having the rocket shoot at least 10 meters in the air. What we have left is to insert an egg into the picture and see if it is carried down without being harmed.
 * Design Challenge Journal Entries**

media type="custom" key="5345625" Investigating Batteries Lab **
 * Proof of working rocket! (Video)**
 * Creating A Controlled Lab Experiment Writeup