Hey Ray! Explaining How Inertia Works

PITTSBURGH (KDKA) -- You may have heard the scientific expression "An object at rest stays at rest."

This is the first part of Newton's first law of motion.

The whole expression states that an object at rest remains at rest, and an object in motion will stay in motion in the same direction and speed, unless acted on by another force.

While that may sound boring, this scientific principle is responsible for some pretty cool experiments.

One of the most famous is the magic trick where the magician pulls a tablecloth from under a table setting, and the table setting stays put.

The objects on the table are at rest, their inertia will cause the to remain at rest, if the trick is performed correctly.

This is a trick, however, that should NOT be performed using nice things because the probability of breaking dishes is VERY high with this experiment.

That said, the tablecloth being yanked causes very little motion to the plates.

Scientist's note: We broke dishes mastering this experiment/trick.  Also, you need a very smooth tablecloth (we used a sheet) with no hem on the corner.  That will create a force that will wreck your experiment.

There is an easier version of this experiment that brings less of a chance of breaking expensive things.

Get a glass of water, an egg, a toilet paper or paper towel roll and a piece of cardboard.

Set the carboard on the glass of water. Set the paper towel roll on the cardboard. Place the egg on top.

Since the glass of water and the egg have more mass, they have more inertia, it takes much more of an outside or opposing force to move those than it does for the lighter cardboard or paper towel tube. They have less mass or less inertia.

This means, that you can hit the cardboard off to the side. Since the Paper towel tube has little inertia, it will get knocked out of the way, too.

The egg and water, with more mass will want to stay in place. Gravity, or an outside force, will take over and cause the egg to drop straight down into the glass of water.

Scientist's note: We broke several eggs mastering this experiment/trick.  Lining up the tube with the glass is what caused our mishaps.