Drop a mass through the 1.5 m tube. It takes about half a second to drop. Then drop a magnet with an identical mass. It takes over 10 times as long to fall. As the magnet falls, it generates a current in the tube, moving in one direction above the magnet and in the opposite direction below. Both currents obey Lenz’s Law and induce magnetic fields that oppose the magnet’s motion. See the difference in weight as the magnet falls through the tube.