Figure 1 illustrates that a rocket engine works in the same way as a jet engine or a balloon in that it releases gas out the exhaust, producing thrust, which in turn pushes the rocket in a direction opposite to that of the escaping gas. The scientific principal upon which this is based is called Newton's Third Law of Motion. This Law states that for every action, there is an equal and opposite reaction.  (

Balloon Cars

Balloon Cars rely on Newton's Laws of Motion.  As the air rushes backward out of the balloon it pushes the car forward in the opposite direction with an equal force. Your job is to make the most of this force!


The rules to this activity are simple:

·         The car must be powered by balloons (I will provide only 1)
·         You can build the car out of anything.
·         It must have at least three wheels. Wheels are defined as anything that is round and goes around.
·         The wheels cannot be wheels from a toy car. They must be made out of something that was not originally meant to be used as wheels.
·         The car may not leave the ground.  It has to stay on the wheels.
·         The car must be capable of traveling at least 5 feet.



Think about:

  1. Why does the car/balloon move opposite of the air?
  2. What causes the car to go (or not go)?  What causes it to stop?
  3. Why do some cars go faster?  Farther?