Science Buddies: "Ask an Expert"

Does anyone know a simple explanation of a boundary value problem relating to the physics of sound? If there is a good website please let me know.
Thanks!

Hi scotta740,

I did some web searches and was unable to find a simple solution. Unfortunately the sites I found include integrals and partial differential equations, both are college level material. Maybe someone else can help.

Hi Scott,

A boundary value problem means what happens at one boundary of a region under investigation affects what happens throughout. An example involving sound would be the vibrations (sound) of an enclosure of air when something is done at a boundary. Think of what happens when you blow across the top of a partially filled bottle or when you hit a drum with a drumstick. An organ pipe is another example. You can look up explanations of all these effects.

Let us know how you are doing with your project.

Mike

A great example of a boundary condition for sound is an air water boundary. Because water is denser than air at the same pressure and temperature, sound propagation changes at the boundary. The speed of sound in air and in water differ. If you look up how light waves behave at surface boundaries (e.g. 100% reflection, partial reflection and partial transmission, etc) and then apply this same insite to how sound waves behave.