5H40.75 - Faraday Train

Code Number:
Demo Title:
Faraday Train
Forces on electrically conducting magnets
Area of Study:
Electricity and Magnetism
Copper Coil made from # 22 wire with relaxed length up to 2 meters long, AAA batteries, 1/2 inch diameter - 1/4 inch thick magnets.

Place a magnet on each end of a AAA battery.  Make sure that the same poles face away from the battery ends.  Take the copper coil off of the PVC storage pipe and lay it in a circular path on the lecture table.  Make sure that there are NO magnetically attracted devices or table mounts anywhere near the path.  Insert one end of the battery assembly into the coil and it should move to the other end of the coil.  Turn the battery around so that the opposite pole goes in first if it does not easily go into the coil.

  • Stephen Irons, "The dipolar express: An electromagnetically driven train", TPT, Vol. 53, #3, March 2015, p. 186.

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