Meters Spool

Physics help: create a car that harnesses wind energy to propel forward.?

For my physics class I need to create a car that will harness the wind energy produced by a 20 in box fan. We are thinking that you would need to use some sort of windmill to harness the energy. The car has to use the wind from the fan and somehow move towards the fan. The only materials we can use is coat hangers, staples, glue, tape, index cards, file folders, tin or aluminum cans, rubber bands, string, thread spools, pins, paper clips, and a maximum of one BIC pen. The wheels can be created out of anything circular other than an actual wheel. The fan will be about 1 meter away from the car and the car must travel a minimum of half a meter. Any type of help would be greatly appreciated. Thanks!

Intertesting interesting question.

The thing that is intreging is the fact that it must move towards the fan. I have thought of two possible ways.

1. I'm nut sure what a box fan is. If it is a more or less open fan and you can feel the air flow from the reverse side, it should feel like it is moving towards the fan, so you could just turn the fan away from the car and let the fan suck the car forward.

2. I don't know if this would work or not but if the fan produced enough wind, construct a sail that would catch the wind. Attach the sail to the car. Attach rubber bands between the car and the fan. Let the rubber bands stretch out as far as the will moving the car away from the fan to start with. Then turn off the fan.

The stored PE in the elestic bands will snap the car back towards the fan thus fulling the conditions of the problem.

As to the construction of the car itself, your imagination will be able to help you along with that, but maybe wheels made from thread spools would be the most efficient and axis and the mast could be made from coat hangers.