The Soda-Bottle Rocket Egg Launching Mission

 
1. My 3 Questions

• What type of physics related material is a part of this project?
• What materials do you need to build the best rocket?
• will this project help us understand concepts better?

This project answered my concepts question. It was nice to see an actual visual of what was happening with acceleration, force, momentum and gravity.  It's one thing to do them on paper with worksheets, but being able to figure out what angle and how much water goes into the rocket to see how far it would go with the wind acting as a force was really cool.

2. To make our rocket we used 2 plastic 2 liter soda bottles, balsa wood, duct tape and super glue. First we cut  one of the 2 liter bottles in half to make a compartment to hold the egg in. Then we cut the balsa wood, which is very light and thin, into 3 triangular wings.  Next we put glue on the bottle where the fins would go. After we glued the fins on, we put duct tape on them as well to make sure they were secure. Our rocket was simple, but it made it way past 30 meters.

 

 

3. The physics of the rocket

Before the rocket is launched it is filled up with 675 ml of water and air pressure of 80 psi is pumped into it.The pressure that is pumped into the rocket makes it shoot up in the air once the rope is pulled to release the air and water out.  The water is released because the air pressure pushes out on it which makes the rocket accelerate and fly into the air.  During take off, Newton's third law of motion, every action there is an equal and opposite reaction, is taking place.  After the rocket accelerate for a few moments it eventually looses its kinetic energy when it reaches the highest point and its acceleration is at 0 now. It will also lose its velocity because it has nothing acting on it topush it higher, only air resistence to slow it down.  Once that happens, gravity pulls the rocket down and the potential energy of the rocket is at its highest. To reduce air resistence we put fins on our rocket so that it wouldn't slow our rocket down as much.  To make sure the rocket went far, we made sure it had enough weight on the top.
 

4. To protect our egg we put it in a ziploc baggie with protein powder and sawdust.  Around that, we put foam to protect it from a hard impact so it wouldn't move around and it the sides of the bottle. At the top of the rocket where it would come into contact with land first, we left some air and put a foam circular mat so that when the impact happened the force would only push the air at the very top and the foam would absorb the blow before reaching the egg.  This plan was a failure.

5. Results

• Distance: 67 meters
• Egg: dead
• Angle of Launch: 45 degrees
• Water: 675 ml

We chose to launch our rocket at 45 degrees and fill it with 675 ml of water because the most successful rockets from the past used those same measurements.  Our rocket went far all three launches using these measurements. Howevere, our egg died all three times because we experimented each time with different materials, but nothing seemed to work. The first two times we used bubble wrap and cotton which failed. I think if we would've made a cone it would have absorbed the impact better and saved the egg.

6. I learned a lot more about how everything we have learned in physics can all come together in one project. I learned that if you put the right amount of water, pressure and a good angle then your rocket will go farther. I'm a visual learner so by actually seeing how force, gravity, acceleration, potential energy, kinetic energy and momentum come together helps me grasp what is going on.  So much happens in just a short amount of time, but it's everything we have learned this semester.