Watch how slowly the magnetized plug drops through the tube!

Experience the fundamental principle behind electric motors with this demonstration. Drop the strongly magnetized plug through the copper pipe, and induced currents cause it to fall very slowly. The unmagnetized plug falls without resistance. The viewing window lets you see the action. Experiments and information included. Lenz's Law Apparatus allows you to demonstrate electric and magnetic forces. Electric current generated by a moving magnet will always oppose the original motion of the magnet that created the current. Amusement Park thrill rides use this same principle for braking.