Rockets, jet engines and spaceships are all driven forward by the same principle: every action has an equal and opposite reaction. This means pushing something out of the back of a rocket will give the rocket a forward push of the same force. In the case of rockets and jet engines the material pushed out the back are the hot expanding gases from the burning of jet or rocket fuel.
You can build your own "cool" rocket by using air stored under pressure in a balloon. When the air is released it will give your rocket a forward thrust.
STEP 1: Get a balloon, some tape, a drinking straw and a length of string at least ten feet long.
STEP 2: Put the string through the straw and then tie the string at each end to something (like door knobs at opposite sides of the room). Make the string taut. This will be the guide track for the rocket.
STEP 3: Blow up the balloon. When it is inflated hold the end closed and get a friend to tape the balloon to the straw so that the end of the balloon is pointing the same direction as one of the ends of the straw.
STEP 4: Back your balloon rocket up so that the balloon end is close to one end of the guide track string.
STEP 5: Launch your rocket by letting go of the end of the balloon. The air escaping out the end of the balloon gives the rocket a forward motion down the string.
Copyright Lee Krystek 1996. All Rights Reserved.