Descriptif

Prerequisites: PHY101, PHY102, PHY201, PHY202

The course provides an introduction to waves in fluids. A necessary first step is to derive a minimal set of equations for fluid motions. In consequence, the course constitutes a partial introduction to fluid mechanics, restricted to inviscid fluids. One goal of the course is to demonstrate how one proceeds to obtain wave solutions starting from a physical description of a system and its equations of motion. Two families of waves are derived and examined in detail: acoustic waves and surface gravity waves. These serve to discuss key notions regarding waves: the methodology to obtain wave solutions, the dispersion relation and its implications, the phase and group velocity, the polarization relations. The above constitutes the core of the course. In complement and as openings to other topics, the three last sessions discuss nonlinearity, different families of waves present in the atmosphere and ocean, and propagation into an inhomgeneous medium.

At the end of the course, the students will understand how to obtain, in a given system, wave solutions if they exist, and how to characterize a family of waves. The illustrations, for acoustic waves and for geophysical waves, will have introduced general culture elements regarding music and musical  instruments, and certain oceanic and atmospheric motions.