Despite billions of dollars and euro being spent on space travel, building your own rocket doesn’t have to cost a cent. With some household material and a bit of DIY you can spend some quality time with your own team of family scientists building one.
All you will need is:
– A balloon – round ones will work but the longer ‘airship’ balloons work best.
– One long thin piece of string, it should preferably be about 10-15 feet long.
– One plastic straw or something that is similar.
What you need to do with your team is tie one end of the string to a chair, door knob, or some other support and then put the other end of the string through a straw.
Pull the string tight and tie it to another support in the room, make sure the string is taught or at least not bending too much.
Blow up the balloon but don’t tie it at the end. Pinch the end of it and tape the balloon to the straw. Make sure the straw is taped along the length of the balloon. Now you’re ready for your launch and be sure to count down from 10. Let go and watch the rocket blast off!
So how does it work? It’s all about the air and thrust. As the air rushes out of the balloon, it creates a forward motion called thrust.
Thrust is a pushing force created by energy. In the balloon experiment, our thrust comes from the energy of the balloon forcing the air out. Different sizes and shapes of balloon will create more or less thrust. In a real rocket, thrust is created by the force of burning rocket fuel as it blasts from the rocket’s engine – as the engines blast down, the rocket goes up. The project above is a demonstration. To make it a true experiment, you can try to answer these questions:
– Does the shape of the balloon affect how far, or fast, the rocket travels?
– Does the length of the string affect how far, or fast, the rocket travels? l Does the type of string affect how far, or fast, the rocket travels? (Try fishing line, nylon string, cotton string, etc.) l Does the angle of the string affect how far, or fast, the rocket travels?
According to Newton’s Third Law of Motion, every action has an equal and opposite reaction. Therefore, as the gas is released from the balloon, it pushes against the outside air, and the outside air pushes back. As a result, the rocket is propelled forward by the opposing force. This opposing force is thrust.