Balloon-Powered Art Car
Source: Stemoto Original
Harness the power of air! Build a custom cardboard car that propels itself across the floor using the thrust of a deflating balloon, teaching Newton's Third Law of Motion.
Categorisation
Props & Materials Required
- •A piece of thick cardboard (for the chassis)
- •4 plastic bottle caps (for wheels)
- •2 wooden skewers (for axles)
- •3 plastic drinking straws
- •A latex balloon
- •Tape and hot glue
Step-by-Step Instructions
Build the Axles
Cut two pieces of plastic straw slightly wider than your cardboard chassis. Tape them firmly across the bottom of the cardboard. These act as bearings.
Attach the Wheels
Poke a hole in the exact center of all four bottle caps. Slide a wooden skewer through one straw bearing, and push a bottle cap onto each end. Repeat for the back wheels.
Create the Engine
Slide the neck of the balloon over the end of the third plastic straw. Tape it extremely tightly so no air can escape. This is your engine.
Mount the Engine
Tape the balloon engine to the top of your cardboard car. Make sure the open end of the straw points straight out the back!
Race Time
Blow into the straw to inflate the balloon. Pinch the straw shut, set the car on a smooth floor, and let go! How far does your aerodynamic design travel?
Why It Works & Notes
This project perfectly demonstrates Newton's Third Law: For every action, there is an equal and opposite reaction. As the compressed air shoots backward out of the balloon (action), the car is thrust forward (reaction)!
Very safe project. Getting the wheels perfectly straight is the biggest engineering challenge. If the axles are crooked, the car will drive in circles instead of straight across the room!