When a magnet bar falls through a copper pipe, it experiences a force due to Lenz's Law, which causes it to reach terminal velocity. The discussion focuses on an experiment that varies the mass of the magnet bar while keeping the magnetic field constant. The goal is to observe how changes in the mass affect the time taken for the magnet to travel through the pipe. Participants express confusion about the experiment's objectives, suggesting it may relate to homework or project work. The experiment aims to provide insights into the relationship between mass and terminal velocity in this context.