Things you’ll need:6 to 8 drinking glasses of the same size
Food coloring (variety of colors)
2 pencils or metal spoons
What to do:
Line up the glasses next to each other.
Add water in each glass (the first one with the least amount, working your way up to the last one, which should be almost full).
Put a drop of different food coloring in each glass. Using the pencils or regular metal spoons, have your child tap the glasses to hear the different sounds produced.
Point out, too, how the water forms ripples as your child taps the glass.
The Science behind it:Because of kinetic energy, the food coloring’s molecules move and mix with the molecules of water—the small amount dissolves into the greater amount of molecules. This movement allows the mixture to even up the solution’s molecules of part food coloring and part water.
As the glass and water vibrates, it creates a sound.
As more water is added, the glass-water vibrating “instrument” gets bigger and denser—the denser the vibrating object, the slower the vibration, thus lowering the sounding pitch.