Things you need:

Balancing 12 nails on the head of ONE

• A block of wood or Styrofoam (4 inches square and about 1/2 an inch thick)
• 12-14 identical nails with heads.

Floating fork and spoon

• A spoon
• A fork
• A matchstick (preferably square-bodied)
• A wide-mouthed glass with water in it

The Experiment:

Balancing nails:

Hammer one of the nails in the wood or Styrofoam. Lay one nail on a flat surface and place other nails across this nail, head to head. Then place another nail on top of this assembly, head to tail with the last nail. Carefully pick up the assembly and balance it on the upright nail in the board. That last step takes some practice.

Fork and spoon:

Obtain a large glass that has quite a bit of mass to it. It is especially good if the glass has a wide mouth with a tapered bottom.

Fill the glass at least half full of liquid because the entire weight of the silverware will be supported on one single point on the outside edge of the glass.

Take the fork and spoon and "hook" them together using the first and last tines of the fork to overlap the spoon. The handle ends must both point in the same direction, making a boomerang-like shape when the two are connected together.

Place the matchstick in the most central position possible between the fork and spoon. Ensure that it is still touching the spoon. Leave as much of the matchstick sticking towards the center of the "boomerang" shape as possible.

Take your fork-spoon-matchstick and balance the matchstick on the edge of the glass with the two handle ends pointing back towards the glass. Note that the matchstick will be horizontal. This part will take some practice as well.

So that's how it works…

The science in balancing the nails and the fork-spoon has to do with their "center of gravity" or balancing point. Gravity pulls any object down as if all of its weight were concentrated at one point called the "center of gravity." Objects fall over when their center of gravity is not supported.

The stability of the objects in both experiments depends on their center of gravity being right at or directly below the point where they are balancing. In both cases, the formation of the object puts their combined center of gravity directly below the standing nail head or matchstick.

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