Resumen de Lenz's Law Demonstration Using an Ultrasound Position Sensor
One of the very popular demonstrations used in introductory physics courses to illustrate Lenz's law is the �slowly falling magnet.� In its simplest version it requires only a powerful cylindrical magnet and a metal tube, typically of copper or aluminum. When dropped in the tube the magnet takes significantly longer to reach the other end than a geometrically similar but nonmagnetic object. This demonstration has been adapted for use in large classes using a camera to monitor the magnet as it approaches the end of the tube.1 Small versions that can be used for hands-on experiments also have been developed2 or are available commercially.3 This classical demonstration in its various forms almost never fails to impress first-time viewers
