What is Waving and Why? The Anatomy of the Wave Equation – Part 1
This is the first of what hopefully will be a continuing series of articles dealing with the fundamental physics of sound waves. Unlike electromagnetic waves that can exist in a vacuum as well as in material substances, sound waves are mechanical waves and require a material medium in which to exist. The medium may be either a solid such as a bar of steel or a fluid such as water or air. Fluids are distinguished from solids in that a fluid will assume the shape of the container in which it is placed. If the fluid in question is a liquid of small volume, however, it will not occupy all of the space provided by a container of larger interior volume whereas a gaseous fluid will occupy all of the interior space provided by the container. In the process of doing so, the pressure, temperature, and the energy content of the gas must undergo adjustments to make this possible.