Sound is a pressure wave carried through solids, gases, or liquids, causing vibrations at varying frequencies detectable by auditory systems in humans or animals. Perception of hearing varies from one species to another, with some species unable to detect vibrations at certain frequencies. In terms of the physics behind sound, the vibrations cannot travel in a vacuum. They need some form of medium or matter to travel through, such as a solid or gas. The types of waves transmitted vary based on the medium through which the sound waves travel. For example, solids transmit both longitudinal and transverse waves.
The following resources provide further information for the study of sound and the physics involved.
Georgia State University. Basic explanation of beat frequencies with diagrams.
MIT Open Courseware. Brief overview of beat frequencies, definition intended for high school students to better understand the concept, includes links to graphs.
University of Wisconsin. Procedures for demonstrating the concept of beat frequencies. Scroll to section 3.6 for beat frequency exercise.
Lawrence Livermore National Laboratory. Lab run by University of California for the U.S. Department of Energy. Article discusses various physics behind sound, including beat frequency.
NASA. Explanation of various sound principles including the Doppler effect.
National Weather Service. Exercise suggested by the NOAA to demonstrate the Doppler effect in terms of weather prediction.
University of Tennessee. Basic overview of the Doppler effect and Doppler shift formulas.
Boscobel Elementary School. Concise, easy to understand discussion of the Doppler Effect
Law of Octaves
Western Oregon University. Discussion of Newland’s use of the Law of Octaves (musical scale) in the development of the periodic table.
Law of Octaves. Simple explanation of the Law of Octaves in non scientific terms.
Bio Waves. The history of sound, discusses a mention of Newland's Law of Octaves and the formula it followed.
Longitudinal Wavelength of Sound Waves
Idaho State University. Transverse and longitudinal waves.
Cornell University. PDF document discussing experiments for longitudinal waves and wavelength.
University of Virginia. PDF lecture on longitudinal waves.
The Physics Classroom. Explanation of longitudinal wave and the anatomy of a wave.
Mechanical Sound Pressure Waves
University of Alabama Huntsville. PDF of a presentation explaining mechanical sound waves and pressure.
NSBRI. How the ear works to pick up mechanical (pressure) waves.
Michigan State University. PDF document covering mechanical waves and other sound-related information.
U.S. Department of Labor. The physics of sound, including sound pressure weighting.
Natural Resonance Quality
Natural Resonance. Overview of natural resonance.
Indiana University. What is resonance? Basics of resonance in terms of sound.
National Institute of Standards and Technology. Explanation of Quality factor in terms of resonance.
Illinois Department of Physics. Natural frequency and resonance in structures.
Pitch and Frequency
Indiana University. Breakdown of sound movement, pitch, and frequency.
Frequency, Wavelength, and Pitch. Overview explaining each concept.
How Music Works. Frequency and Pitch, an overview.
NDT Resource Center. Frequency, resonance, and changing pitch.
Sound Intensity and Decibels
Trace Center, University of Wisconsin. Overview of decibels, what they are, and the different types.
University of California, Santa Cruz. Decibels and the various ways to calculate them.
Boston University. Definition and examples of sound intensity and decibels.
Seattle Department of Planning and Developing. Sound intensity and decibels as they relate to Seattle’s Noise Abatement Program.
Speed of Sound
The Soundry. Brief explanation of the speed of sound.
U.S. Centennial of Flight Commission. The Speed of Sound and Mach Numbers.
Princeton University. The speed of sound in water, specifically in ocean waters.
Kettering University. List of links and movie animations concerning vibrational modes.
Acoustics Society of America. Vibrational modes as they relate to specific musical instruments such as a steelpan drum.
Waves Webquest. List of links on a variety of sound wave information, including vibrational modes.
Intute Consortium. Combined project from several UK colleges and universities to create a clearinghouse of information for research into sound and acoustics. Lists several resources, including those for vibrational modes.
How to avoid meeting monotony, be a better speaker, and make your communication sing
This collection of short articles will help you engage with your participants and be a strong, successful speaker. Purchase through Amazon.PURCHASE