Science fair experiments with balloons and rockets can tackle several science topics. You can develop physics science fair projects that look at propulsion systems or the physics of rocket aerodynamics. No matter what you are interested in you will have fun working on these experiments. Have fun with the following sample projects!
Does the size of the balloon impact how high a rocket will fly? This is the first hypothesis that you can test with your science fair projects with balloons and rockets. In this experiment you will build rockets that use different sized balloons to propel them into the air. Does size matter? If yes, is their a formula you can use to predict how high a rocket will go based on the volume of the balloon?
Does the shape of the balloon impact how high a rocket will fly? To test this hypothesis you will need to develop physics science fair projects that use balloons of different shapes to propel your rockets. Use a long narrow balloon, a round balloon and a heart shaped balloon. Make sure that each of these balloons is filled with the same volume of air. Does shape matter? If yes, why. If no, why not?
Does the type of gas that the balloon is filled with impact how high a rocket will fly? This hypothesis will require you to fill your balloon with different gases. The safest ones will be air from your lungs and helium. Use the same size and shape of balloons to test this experiment. The independent variable for this experiment will be the type of gas and the dependent variable will be the distance the rocket travels into the sky.
Can you increase the height a rocket flies by adding additional balloons to its propulsion system? See what it takes to build a pop rocket. For this experiment the number of balloons will be the independent variable and the distance the rocket flies will be the dependent variable. Does the number of balloons impact how high a rocket will fly? Why or why not?
All of the above science fair experiments with balloons and rockets are fun and produce interesting results. Your job now is to expand on these experiments and to make them your own. To advance these projects you will want to think about ways that the data collected from the above experiments can be used to solve a problem or to meet a rocket design goal. Have fun, think outside the box and try to create an experiment or project that no one else has.