Golf Ball vs. Lead Fishing Weight

This is one of my favorite demos to show how mass determines the inertia of an object. If you are going to do this demo in class, make sure you use fishing line that can handle the highest tension possible (great demo for tension as well) that you can buy at a local sporting goods store. I used goop adhesive to attach a paper clip to the golf ball, so that I could tie the fishing line to the golf ball. I tied both objects to the metal beams of the drop down ceiling in my classroom. Watch the video to see how the demo works.

Video Demo: Apple Inertia

Inertia is the tendency of an object to resist a change in its motion.  An apple and a knife are moving downward.  The counter-top applies an unbalanced force upward on the knife.  The knife decelerates, but the apple does not.  The apple decelerates only when the knife handle applies a force upward on it.

Video Demo: Fishing Weight Inertia

The more mass an object has, the more inertia it has.  Inertia is the tendency of an object to resist a change in motion.  There are two fishing weights.  One has more mass than the other.  A string applies an unbalanced force to the different weights.  Which one resists a change in motion?  Watch the video.

Video Demo: Beaker Inertia

Another demo on inertia?  Yup, and this time I have enlisted the help of one of my favorite science guys: Beaker.  Beaker, books, and a rolling chair are moving at constant velocity until an outside unbalanced force is applied.  Watch what happens!

Video Demo: Ring Inertia

I shot a lot of video before the end of school, and here is a favorite but simple one of mine.  All you need is some chalk (or pennies), a wooden ring (from a craft store), and a flask.  Watch the video.