World’s Easiest DIY Electric Train

Hey, what effect would doubling the number of turns in the coil produce. Or tripling, or quadrupling? And with a chain of batteries, like the trains you (Physics Girl!) made in the video. Or in a weightless environment?  This is an opportunity for controlled experiments! Also, measure speeds (with a CBL motion detector) of the batteries when they exit the coils. Very cool stuff! (From a physics teacher of blind students!)