Comments about Arbor Scientific Lenz's Law Apparatus:

This demo is fairly easy to make yourself, but not having the time to get something together quickly on short notice for new student orientation in Science, I purchased this and some other "hands on" demos from Arbor. This one was one of the more popular. The "bullets" are identical in weight and appearance, capped with protective unbreakable plastic. The tube is windowed along most of its length so you can easily watch the difference in fall rates. Two end caps are included. No "hidden from sight" mystery involved. Nice improvement on an old demo.

Only problem was the end caps are hard to remove at first. But a little lubrication fixes that.

Comments about Arbor Scientific Lenz's Law Apparatus:

The window in the pipe is what makes this demonstration so effective.