Lesson 1: Action and Reaction: The Physics of Thrust
Duration of Days: 2
Lesson Objective
Students will apply Newton’s Third Law to design a balloon-powered propulsion system and explain the energy transfer from potential to kinetic.
1. How can air moving in one direction move a car in the opposite direction?
2. What happens to the "stored" energy in the balloon as it deflates?
Newton’s Third Law, Action/Reaction, Elastic Potential Energy, Kinetic Energy, Thrust.
ENG.05.04: Apply principles of mechanical power.
NGSS MS-PS2-2: Forces and Motion.
Students experiment with "balloon rockets" on a string. They measure how far a balloon travels based on different volumes of air. They then design the "engine" (balloon attached to a straw) for their car.
Purpose: To isolate the propulsion variable before adding the complexity of a chassis and wheels.
DOK Level: Level 2 (Skills & Concepts).
Provide various straw diameters (narrow vs. wide) to allow students to visually see the difference in thrust duration.
Assessment of Understanding: A "Flow of Energy" diagram showing: Stretched Rubber Moving Air and Car Motion.
Balloons, various drinking straws, masking tape, string, stopwatches.