United States

The acoustic impedance is an important quantity in characterizing the behavior of an acoustic system. The acoustic impedance of musical instruments determines the instrument’s response to excitation, reveals resonance frequencies, and shows which notes can be played. While the acoustic impedance is easy to calculate for simple shapes, it is very complicated to do so for the shapes of real musical instruments. This talk outlines an interactive method of calculation of the acoustic impedance of an arbitrary shape of an axially symmetric air column by approximating the air column by a series of cylindrical elements. We demonstrate the feasibility of the method by comparing the iterative result with the closed form solution for air columns of simple shape. Moreover, we discuss the calculation of the acoustic impedance of a trumpet-like instrument and show how different parts of the instrument affect its acoustic behavior.

AAPT SM 20

Iterative Calculation of the Acoustic Impedance of a Trumpet-Like Musical Instrument

physical acoustics

acoustic impedance

computational physics

The 2020 AAPT Virtual Summer Meeting brought together physics educators from around the globe to learn about the latest in physics theory, research methodology and education from leaders in their field. The program featured plenary speakers, sessions, workshops and many special activities.

For more information please visit the 2020 AAPT Virtual Summer Meeting page at: https://www.aapt.org/Conferences/SM2020/index.cfm.


technical paper

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BYU/UVU-GAL: A Focused Outreach Activity for Young Women

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Iterative Calculation of the Acoustic Impedance of a Trumpet-Like Musical Instrument

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