At a recent science convention, we had a display table showing some of the materials developed by the Elementary Science Study. One of the items on display was a small motor, made from one D cell, two fahnestock clips, a rubber band, 16 inches of enameled copper wire, two safety pins and one small flat magnet. The rotor for the motor is made by winding the wire around your finger, leaving the two ends protruding about an inch on opposite sides of the loop, and scraping the enamel off the ends. (See Batteries and Bulbs Teacher's Guide for more details.) There is no commutation for this loop. Why it works has yet to be clearly formulated, and some electrical engineers have told us it will not work.
Reflections on a decade of grade‐school science
Joe Griffith, Philip Morrison; Reflections on a decade of grade‐school science. Physics Today 1 June 1972; 25 (6): 29–34. https://doi.org/10.1063/1.3070890
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