Action-Reaction! Rocket
Students construct rockets from balloons propelled along a guide string. They use this model to learn about Newton's three laws of motion, examining the effect of different forces on the motion of the rocket.
Students examine rocket motionCopyright NASA. WIkimedia Commons https://commons.wikimedia.org/wiki/File:Launch_of_Juno.jpg
Engineers of all disciplines apply their understanding Newton's laws of motion to quantify the "invisible" forces acting on all objects. Just like a ball can be twirled on the end of a string, satellites and spacecraft stay in orbit around the Earth due to the balance between gravitational and centripetal forces. Eventually, satellites slow down due to the miniscule drag in the upper atmosphere, to the point at which gravity pulls them out of orbit. To keep them in orbit, engineers exploit the second law by designing thrusters that burn fuel and expel it from the thruster. The spacecraft moves forward in an amount equal to the force of the gas leaving the thruster, causing enough movement to re-orient the path of the object and keep it in orbit.
After this activity, students should be able to:
- Explain practical applications of Newton's laws of motion.
- Use a balloon model explain the different forces that act on the rocket.
- Collect data from the experiment and graph the results.