Physics of Sound http://www.kaneva.com/asset/assetDetailsLandingPage.aspx?assetId=4377687&communityId=0 A wave is a disturbance from which mechanical energy is transferred from one point to another through a medium. The mechanical energy is transferred by pressure or a source that causes the original wave in the first place. The mechanical energy is transferred through a pressure and then release of the energy compressing and displacement of the particles in the medium that it is being transferred through. It is similar to how a spring transfers energy through out it's coils. This mechanical energy is generally generated by vibration. That vibration then causes the particles in the medium to compress. Particles then react with the other particles in the medium transferring the mechanical energy from one to another. The original vibration pushes the beginning particles out of equilibrium through compression and displacement. The wave moves through the medium by the interactions of the particles in the medium and constant shifting of particles in the medium to go in and out of equilibrium as the mechanical energy is transferred till it is absorbed. In this case the ear absorbs the mechanical energy caused by the source of the sound wave and converts it into an electrical signal to the brain.