Egg Drop - Newton's Law of Inertia With a single whack, the pan and tube go flying and the egg lands in email to friend
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1. Fill the container about three-quarters full with water and center the dinner plate on top of the glass. Place the cardboard tube on the plate, positioning it directly over the water. Carefully set the egg (or practice ball) on top of the cardboard tube.
2. With your writing hand, smack the edge of the dinner plate horizontally. Make sure you follow-through. (Tennis, anyone?) It’s important that you use a pretty solid hit so plan on chasing the plate and tube.
3. Your astonished guests will watch the egg plop nicely into the water. It’s even more fun to watch someone else try to drop the egg. Science is so cool!

How does it work?

Credit for this one has to go to Sir Isaac Newton and his First Law of Motion. He said that since the egg is not moving while it sits on top of the tube, that’s what it wants to do: not move. You applied enough force to the plate to cause it to zip out from under the cardboard tube (there’s not much friction against the container). The edge of the pie pan hooked the bottom of the tube, which then sailed off with the plate. Basically, you knocked the support out from under the egg. For a brief nano-second or two, the egg didn’t move because it was already stationary (not moving). But then, as usual, the force of gravity took over and pulled the egg straight down toward the center of the Earth. Also according to Mr. Newton’s First Law, once the egg was moving, it didn’t want to stop. The container of water interrupted the egg’s fall, providing a safe place for the egg to stop moving so you could recover it unbroken. The gravity-pushed egg caused the water to splash out. Did someone get wet?

You could test longer tubes, more or less water, different liquids in the container, and heavier or lighter falling objects. So much science and so much fun!