Like clarinets and saxophones, flutes are woodwind instruments. The column of air in a flute, however, is not set in motion by a vibrating reed. Instead, the flutist must blow across the opening of the mouthpiece. When the stream of air flows through this hole at the right angle, it produces a soft “whistle”. As this whistle travels through the body of the instrument, it is shaped into the rich, warm tones of a flute.
Things Required:
Several plastic soft drink containers
Water
Ruler
Directions:
Clean and dry an empty soft drink container. Place the neck of the container just below your lower lip. Curl your upper lip outward so that it may direct a stream of air at the opening of the neck. Vary the force of the air jet (and its angle) until a rich sound is produced by the flowing air.
Fill a second bottle about half full of water. Before you produce a sound with this container, make a guess. Will this note be higher or lower in pitch than the note produced in the empty container? Test your prediction.
Magic Words:
If you have three identical containers and three friends willing to join in, you can form a pleasing musical chord. Keep one container empty. Fill another container one-fifth full with water. Fill the third container one-third full of water. Play the three notes at the same time. You may have to “tune” the containers slightly. This can be done by adding or removing water.
This Is What Happens:
As you blew into the bottle, you set the air in motion. As the particles of air moved back and forth, they formed a sound wave. This sound emerged from the neck of the bottle as a distinct note.
Water that was added to the container filled up some of the space. Since the column of air was shortened by the rising level of water, it produced a sound of higher pitch.
