Will a bar magnet fall slower and reach terminal velocity in a vertical copper or aluminum tube but not in a cardboard tube?
This is actually a really cool thing to watch. If the copper is think enough, the magnet will just have a very small terminal velocity, so it appear to float down the tube. As the magnet moves down the pipe, it we have a magnet field that is changing in time. This causes an electric field, which causes a current inside the copper tube. The current creates a magnetic field in the opposite direction of the one that created the current, so now there is a magnetic field opposing the magnet. This creates a force upward against the motion of the magnet. This is what causes the magnet to reach terminal velocity.
There are probably minute parts of ferrous matter in the aluminum and copper, so it would fall slower because it would be attracted to these particles, but the differences probably couldn't be measured too tiny
