Balloon-Powered Car – Experiment

There are various energy sources in the world and one of which is air. But can air power something like a car? That’s what we’re going to find out with the balloon-powered car experiment. Because after all, balloons can hold a lot of air inside them. Making your own balloon-powered car is a ton of fun, but will require an adult to help! On top of that, there’s a few things you will need first:

You will need:

  • A base for your car (e.g. a plastic bottle or cut-out piece of cardboard)
  • Wheels for your car (e.g. 4 plastic bottle caps or carton lids)
  • 2 or 3 drinking straws
  • Tape
  • Scissors
  • A balloon
  • A long wooden/bamboo skewer (or 2 short ones, optional)
  • Penne/Rigatoni pasta (if you don’t have a wooden skewer)

Method:

  • There are various ways you can begin to create your balloon-powered car, but based on our own trial and error, we think it’s best to begin with the base and balloon. If you’re using cardboard, be sure to cut it into the shape you want for the car beforehand.
  • Once you’re happy with your design, you’ll next want to take the balloon and trim the mouth off. Place the tip of one of your drinking straws inside the balloon and tape the two of them together, making sure there are not gaps where air can escape. After all, this will be what will “power” your car.
  • Next, we need to attach the balloon and straw to the base of your car. If you’re using a bottle as a base, be sure to firstly remove the lid. You’ll need to cut a hole at one side of the bottle so that the straw can poke though it and the end of the straw without the balloon can poke through the top of the bottle. Alternatively if you’re using cardboard, simply tape the balloon and straw onto the top of the base. With either method, you’ll need to make sure that the straw is facing behind the car and you can easily access it with your mouth still.
  • Halfway there, now we can start on the wheels and axle! Again, we can use multiple methods to do this. If you have a wooden/bamboo skewer or two, cut them so that they’re slightly longer than the width of your car. After that, take your remaining straw and cut it in half, placing your wooden skewers inside of each half. If you DON’T have a wooden skewer, you can instead create your axle out of straw and pasta. With this method, we’d be placing the straw inside the pasta, making sure the straw is longer than the width of your car. Just to note, this isn’t the recommended way of doing things, but can be an alternate if you don’t have wooden/bamboo skewers as long as you have sturdy drinking straws available.
  • With your axle complete, it’s time to attach the wheels. To do this, you’ll need to take your scissors and pierce a hole in each of the bottle caps/carton lids. The hole doesn’t need to be very big, but will need to be a large enough size to fit your skewers/straws into. Finally, attach your wheels to each end of the two axles and tape them both underneath the base of your car.
  • Now, your balloon-powered car is ready to be tested! Since there’s been a lot of steps to follow, it’s important to make sure the car works how it should. You can first begin by rolling the car along it’s wheels first, making sure they turn as they should. After that, it’s simply a case of blowing into the balloon that’s attached to the car and making sure it pushes the car along when the air is released. Assuming your tests go along smoothly, that’s the balloon-powered experiment complete!

The Science Bit:

Despite the amount of steps this experiment took to finish, the science behind the balloon-powered car is very simple. In the same way a balloon would usually travel a fair distance when the air is released, the same applies here. In this case, the car is being pushed-along by the compressed air releasing from the balloon. This is the energy of motion, called kinetic energy. The air being stored in the balloon is an energy source for the car and is turned into kinetic energy when released. After all, since balloons are elastic they can store more potential energy inside of them. And that’s that – I hope you enjoyed the balloon-powered car experiment!