Float Your Metal Boat
Next time you have to clean some dishes in the sink, try getting your hands dirty with a little science.
What You Need:
1. a piece of aluminum foil
What You Do:
1. Cut the aluminum foil into the shape of a powerboat. Just make up a shape. But keep your boat only about 4 cm wide (about 2 inches) and about 10 cm long (about 4 inches).
2. Gently place the boat into a sink full of clean water (no soap).
3. Squeeze a drop of dishwashing liquid onto the water behind your boat.
The boat moves. The soap breaks up the surface tension in the water behind the aluminum foil. The surface tension pulls the boat forward. Some pond insects can skim along the surface of the water in the same way. They’re light enough that surface tension can hold them up, and they use their legs to break up the surface tension just enough to move.