Out of my 3 cars, the car with the slanted face traveled the greatest distance. My hypothesis proved correct under these conditions. Bringing up the rear was the car with a piece of cardboard in the front, standing straight up. The car with the straight fin in front was creating too much air pressure in front, rapidly decreasing its speed. We will have no means of power except for electricity, and magic.
Electricity is more reliable.
Materials 3 rectangular pieces of wood. Wood glue hand saw marking pencil 2 long planks of wood Large elastic cord. I will assemble the 3 cars according to what I am testing. Place the planks of wood on pool table. Attach elastic cord to planks.