One good sound wave experiment is the cups and string experiment, which requires two plastic cups, a long string, two paperclips and something to make holes in the cups. Punch holes in the bottom and center of the cups, then thread each end of the string into the cups from the bottom and attach the paper clips. Pull the cups apart until the string is taught. Speak into one cup and listen from the other.Continue Reading
The next experiment demonstrates how sound resonates. Take two identical glasses, and fill them each with the same amount of water. Take a wire 1/2 inch longer than the diameter of the rim, and place it over one of the glasses, bending the wire down on each side. Rub the rim of the non-wired glass, and observe how it's affected due to the sound resonance.
For the last experiment, mix 1/4 box of corn starch with 1/2 cup water in a mixing bowl. Adjust the mixture until it is the consistency of honey. This creates what is known as a non-Newtonian fluid, a fluid that turns solid when sufficient pressure is applied. Lay a speaker on its back and cover it with saran wrap, creating a bowl over the speaker. Gently pour the mixture into the bowl. Find a frequency generator online to experiment with cymatics. Start at low volume and a higher frequency. As the frequency is lowered, the mixture begins to lose its geometrical patterns and develops finger-like growths. Raise the frequency and lower the volume again to watch it reliquefy.Learn more about Optics & Waves