Can the force and direction of the air from the balloon ov ercome axles that are not parallel, and make the car go straight rather than on a curve?
Once students get their cars to roll, there are still likely to be some issues. A major one will probably be that many cars will not travel in a straight line. Ask students:
- If you’re pedaling a bicycle or tricycle, or pulling a wagon, what do you need to do to make it turn?
- What has to happen for a wagon or tricycle to go straight?
Use charts to develop the idea that a vehicle go straight if the two axles are parallel, and will go crooked if the axles are not parallel. See diagrams below: