A plastic soda bottle partially filled with water is pressurized with air using a pump. When released, the escaping air and water propel the bottle upward, demonstrating Newton’s Third Law of Motion and the relationship between force and acceleration.

1. Construct or purchase a pop bottle rocket launcher and set it up in an open outdoor area.
2. Attach fins and a nose cone made from lightweight materials (such as cardboard or foam) to a 2L pop bottle.
3. Pour about 300–400 mL of water into the bottle.
4. Secure the bottle onto the launcher nozzle, making sure it is locked in place.
5. Ensure all observers are at least 3–5 meters away.
6. Assign one person as the “pumper” and another as the “launcher”.
7. Use a hand pump to add air pressure into the bottle, not exceeding 40 psi.
8. Conduct a countdown and release the launch mechanism to propel the rocket upward.
9. Observe the rocket’s flight path and landing.

DIY STEM Project For Kids: How To Make A Bottle Rocket - Virtual Club:

Science at Home - SE1 - EP18: Water Bottle Rockets - The Sci Guys:

📄 Pop Bottle Rocket, Part I: Action and Reaction - Science World: https://www.scienceworld.ca/resource/pop-bottle-rocket-part-i-action-and-reaction/

• Try different bottle sizes to see which travels higher.
• Experiment with fin shapes and nose cone designs to improve stability and flight path.
• Vary the amount of water in the bottle to investigate how mass affects flight.
• A ball pump and a cork can also be inserted straight into a soda bottle partly filled with water, but the person launching will get wet.
• Try fitting a parachute to the bottle.

• Do not launch indoors.
• Always supervise launchers.
• Maintain a clear safety zone around the launcher.
• Be careful of the bottle tipping over, it can fire at people with a large force.
• If the bottle doesn't launch then release pressure before touching.
• Watch the entire rocket flight to avoid accidental impact.
• Retire bottles after a few flights or if damaged.

• Would larger or smaller soda bottles go higher? (Larger bottles can hold more air, but may also be heavier; results depend on design.)
• How could we measure and compare the rocket heights? (Using a meter stick, a marked pole, or by timing flight duration and estimating height.)
• How does increasing the air pressure affect flight? (Greater pressure produces more thrust, leading to higher acceleration and flight.)
• What role does the amount of water play in the rocket’s performance? (Too little water reduces thrust, too much water adds mass; an optimal balance is needed.)
• Why does the rocket fly straighter with fins? (Fins stabilize the rocket by reducing tumbling and helping it maintain direction.)