Rocket Reactions

Rockets in History Rockets and rocket-propelled flight has been in use for more than 2,000 years. People in ancient China used gunpowder to make fireworks and military rockets. In the past 300 years, people have gained a scientific understanding of how rockets work, starting with Sir Isaac Newton.

Rockets Today Now, aerospace engineers use their understanding to make rockets fly farther, faster, higher, and more accurately. Rockets are now used for fireworks, weaponry, ejection seats, launch vehicles for artificial satellites, human spaceflight, and space exploration.

Check this out…

What did you observe? What caused the rocket to move? What direction did it move? Were there any other things moving? Did the gasses/fuels move in the same direction as the rocket?

Observe a balloon… Predict what will happen when I let go What direction will the balloon move? What direction will the air move? Draw a balloon in your notes then add arrows on the balloon to show your two answers from above…

balloon movement air movement

Can you explain? What caused the balloon to move once the air was released? Remember Newton’s 1st and 2nd Laws? Were the forces balanced? What two objects were interacting in this demonstration? The balloon and the air inside.

Rocket Reactions Experiment (Demonstration) We are going to launch a balloon across the room, while it is attached to a straw, which is on a fishing line. We want to change only one variable, which is the air pressure inside the balloon. Predict (infer, form a hypothesis) what will happen if I blow the balloon up with more pumps…what do you think will happen to the distance it will travel?

Set up your testing apparatus Conduct 3 trials with 3 pumps of air in the balloon, calculate avg. Conduct 3 trials with 4 pumps of air in the balloon, calculate avg. Conduct 3 trials with 5 pumps of air in the balloon, calculate avg.

Classroom Demonstration…

Rocket Reactions Experiment How does __________________affect _________________? Independent Variable:_________________ Dependent Variable:___________________ Controlled Variable (constants) ________________________________ _________________________________________________________

Gather data then look for a pattern… # of pumps Average Travel 3 4 5

Distance a Balloon will Travel

Analyze and Infer… Draw a model of the forces on the balloon-air system. Are the action-reaction forces equal? How do you know? How does the balloon size relate to action-reaction forces?

Clean up and put everything back where you found it.