there is a contest to build an electric motor for which we can get some bonus points on the final in my E&M class. they give us a very limited kit and we can only use what comes in the kit which is a couple pieces of thick poster board, 6 feet of insulated wire, a couple paper clips, a couple tacks, and 2 magnets. the only object is to make the motor spin as fast as possible (no extra external load). i pretty much have an idea of how i want to build it but im unsure about a few things. what is the optimum coil size? the magnets are circular - should i wind the coil to have the same diameter as the magnets? i figure that if you make it smaller, it will have less area, but you can put the magnets closer to create a stronger field. conversly, if you make it bigger the magnets will have to be farther apart giving a weaker field but there will be more area - more flux. what do u guys think? also, does it matter how neat you wind the coil - any certain technique or pattern for winding it that will make it run faster? also any other suggestions are appreciated. thanks.