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Does money dance?

Can money make people dance?

This experiment tries to answer the first question only.

The answer to the second is probably best discovered by booking tickets to a show or ballet in your city or a nearby town. If either proves difficult, watching a musical is another way of answering the question.

That could be almost as much fun as doing an experiment!

Lay the coin flat over the opening of the bottle. You may need to try different coins and bottles to find an acceptable combination. (To increase the effect of this experiment try chilling the bottle for a few minutes first.)
Drip a few drops of water or cooking oil on top of the coin until it drips over the edges to form a seal between the coin and the lip of the bottle.
Wrap both hands around the body of the bottle.
The coin will begin to “dance” or tap on the lip of the bottle. If the coin does not tap, air may be escaping between the coin and the lip of the bottle. Add a few more drops of water or oil.

What happened?

What happened was the heat from your hands warmed the inside of the bottle. In a closed container of any gas, there is a direct relationship between temperature and pressure; as temperature increases, so does pressure. The pressure increase is caused by the increase in motion of the gas molecules as they become warmer. The added energy (provided by the warm hands) increases the motion of the gas molecules until they lift the coin. As some of the gas escapes, the coin raises a bit - then drops back down. This is the “dancing effect.