A New Twist on Resonance in a Tube

Understanding resonance is key to making sense of a wide range of physical phenomena. I will illustrate a simple and inexpensive way to allow students to explore resonance using equipment that many high schools and colleges already have available. The benefits of this method include: (1) Students get clear, convincing data without much difficulty, (2) Students are themselves the sound sources, bringing the experiment from ``what lab apparatus does'' to ``how the world works'', (3) Students work through the meaning of a visual representation of sound as they predict how altering the setup will affect the representation, (4) Students use their data to find the speed of sound in air to within a few percent of the standard value. With the appropriate emphases and level of analysis, this experiment is suitable as a lab for college students, a lab for high school students, or as a demonstration.