Thanks to Erik Petersen for consulting on this project.
*Note:
For this science project you will need to develop your own experimental procedure. Use the information in the summary tab as a starting place. If you would like to discuss your ideas or need help troubleshooting, use the Ask An Expert forum. Our Experts won't do the work for you, but they will make suggestions and offer guidance if you come to them with specific questions.
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Abstract
Helmholtz resonance, or air cavity resonance, refers to the resonance of air in a container with a small opening, like a plastic bottle or the devices shown in Figure 1. The resonant frequency of the air depends on the volume of the air in the container and the geometry of the opening (its length and cross-sectional area). The Helmholtz frequency is not the same as the natural frequency of an air column in a cylinder, where the opening is the same size and shape as the rest of the cylinder.
You can find the equations for both scenarios in the Bibliography section. Try using these equations to predict the frequency of sounds generated by a musical instrument, or you can make your own simple instruments using plastic bottles. You can measure the actual frequency using a pitch detector or audio spectrogram app on your phone. Which equation is more accurate for various geometries? How close are the results? For example, try comparing wide- and narrow-mouthed plastic bottles, plastic bottles with different levels of water in them, or different notes played on the same musical instrument. How well do your measured results match your predictions using the equations?
You can also analyze the model for Helmholtz resonance in more detail. For example, how do you define where the cavity ends and the neck begins? How much of a difference does this choice make? Try calculating the resonant frequency for high-end and low-end estimates of the neck length. Does the measured frequency fall within these two values?
Nave, C.R. (n.d.). Air Column Resonance. Hyperphysics. Retrieved April 12, 2021.
Nave, C.R. (n.d.). Cavity Resonance. Hyperphysics. Retrieved April 12, 2021.
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Do you have specific questions about your science project? Our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.
Physicists have a big goal in mind—to understand the nature of the entire universe and everything in it! To reach that goal, they observe and measure natural events seen on Earth and in the universe, and then develop theories, using mathematics, to explain why those phenomena occur. Physicists take on the challenge of explaining events that happen on the grandest scale imaginable to those that happen at the level of the smallest atomic particles. Their theories are then applied to…
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Any time you hear music at a concert, a live speech, the police sirens in a TV show, or the six o'clock news you're hearing the work of a sound engineering technician. Sound engineering technicians operate machines and equipment to record, synchronize, mix, or reproduce music, voices, or sound effects in recording studios, sporting arenas, theater productions, or movie and video productions.
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General citation information is provided here. Be sure to check the formatting, including capitalization, for the method you are using and update your citation, as needed.
MLA Style
Finio, Ben.
"Helmholtz Resonance and Musical Instruments." Science Buddies,
5 May 2021,
https://www.sciencebuddies.org/science-fair-projects/project-ideas/Music_p038/music/helmholtz-resonance.
Accessed 7 June 2023.
APA Style
Finio, B.
(2021, May 5).
Helmholtz Resonance and Musical Instruments.
Retrieved from
https://www.sciencebuddies.org/science-fair-projects/project-ideas/Music_p038/music/helmholtz-resonance
Last edit date: 2021-05-05
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