The Ear Drum & The Vocal Cords
Last week in science we tried a couple more fun experiments to deepen our understanding of hearing and sound.
Dancing Salt ~ We were talking about the ear drum and the fact that sound waves travel down the ear canal and cause the ear drum to vibrate. With our dancing salt experiment we tried to demonstrate what this might look like! First we made an "ear drum". We secured a piece of wax paper with an elastic band over the top of a jar. We placed salt on the wax paper. Then we made sounds by beating a drum. We saw that the sound waves caused the salt to vibrate and "dance" around. Sound is energy. Any material that vibrates makes waves (sound waves).
Balloon Vocal Cords ~ With this experiment we were trying to demonstrate how your throat vibrates to make sounds. Blow up a balloon (this is your lungs for the demonstration) pull the top of the balloon tight, and then let the air out. As the air escapes, the neck of the balloon (this is your vocal cords for this demonstration) vibrates back and forth. The result of this vibration is sound! When air pushes past your vocal cords, they vibrate and make sounds. Your voice makes sounds when air causes the vocal cords to vibrate.