Balloon Powered Car

Students construct a simple car powered by the air escaping from a balloon. The activity demonstrates Newton’s laws of motion and the conversion of potential energy stored in the inflated balloon into kinetic energy as the car moves forward.

1. Gather recycled materials such as a lightweight bottle, four bottle caps for wheels, two skewers for axles, straws, tape, scissors, and a balloon.
2. Cut two straws slightly wider than the bottle and tape them parallel to the underside to act as wheel supports.
3. Push skewers through the straws, attaching bottle caps at both ends to form rolling axles.
4. Attach the balloon securely to one end of a straw using a rubber band, ensuring there are no air leaks.
5. Cut a small hole in the top or side of the car body, and feed the straw with the balloon through it so that it points backward.
6. Inflate the balloon through the straw, place the car on a smooth surface, and release the air to propel the car forward.
7. Observe how far and how smoothly the car travels. Make adjustments if wheels are not aligned or if the car veers off course.

How to make a Simple Balloon Powered Car | DIY Air Powered Car | Science Project - Creative fest:

Make a Balloon Powered Car with Plastic Bottle | DIY Air Powered Car | Science Project - Creative fest:

📄 Build a Balloon Car - Ben Finio: https://www.sciencebuddies.org/stem-activities/balloon-car

• Try using different materials for the car body, such as cardboard or foam trays.
• Change balloon sizes to see how air volume affects travel distance.
• Add weights or modify the shape to study the effect of mass and aerodynamics.
• Build multiple designs and hold a race to test which car travels the farthest or straightest.

• Use scissors and hobby knives only under adult supervision.
• Avoid overinflating the balloon to prevent popping.
• Keep sharp skewers pointed away from hands and eyes.
• Work on a clear, flat surface to prevent rolling objects from falling.

• Which force makes the car move forward? (The air rushing out pushes backward, propelling the car forward—Newton’s third law.)
• How can you make the car travel farther? (Reduce friction, increase balloon air volume, improve wheel alignment.)
• What happens when the balloon runs out of air? (The car continues moving until friction stops it—Newton’s first law.)
• How is potential energy converted to kinetic energy in this activity? (Air stored in the inflated balloon provides potential energy, which converts to motion as the balloon deflates.)
• How could you modify the design to carry a small load or move faster? (Experiment with lighter materials, larger balloons, or smoother axles.)