Make a Balloon Racer
Build your very own air-powered vehicle and zoom across the room with these super-fun Balloon Racers!
Materials Needed
- Small plastic bottle (stuffed with tissue paper if desired)
- Wooden skewers
- Plastic bottle caps (pre-drilled with small holes)
- Drinking straw
- Balloon
- Rubber band
- Tape
- Scissors
Step-by-Step Instructions
Step 1: Insert two wooden skewers horizontally through the bottom sides of the plastic bottle to form the wheel axles.Step 2: Press a plastic bottle cap onto each exposed end of the skewers to serve as wheels.
Step 3: Attach the neck of a balloon securely around one end of a drinking straw using a rubber band.
Step 4: Tape the straw and balloon assembly to the top of the plastic bottle so the straw points backward.
Step 5: Blow through the straw to inflate the balloon, then pinch the straw shut.
Step 6: Place the car on a smooth floor, release the straw, and watch your balloon racer speed away!
Learn More
This fast-moving racer demonstrates Newton’s Third Law of Motion, which states that for every action, there is an equal and opposite reaction! When you inflate the balloon, you trap compressed air inside. As soon as you let go, the stretched rubber walls squeeze together, pushing air backward out of the straw. That backward rush of air is the action force. As a reaction, the escaping air pushes back against the car with equal strength in the opposite direction, propelling your racer forward across the room!Ready to explore more air-powered physics and engineering? Check out the Air Hockey kit from the KiwiCo Store to build a balloon-powered air hockey game at home!