Waves of sound.
define the term sound
An oscilloscope is the machine, but it measures frequency.... so sound waves are measured by frequency
Acoustics.
The word is acoustics.
Acoustics is the study of sound and sound waves, including their production, transmission, and effects. It explores how sound interacts with its environment and how it can be measured and manipulated.
The term decibel is a unit of measurement of the loudness of sound. It has nothing to do with light, which is measured in lumens.
Trigonometry is used to define triangles, but it is also useful in the representation of waves. Sound engineers, obviously, use deal with sound waves. The pitch, volume, and direction of a sound wave are all deeply rooted in trigonometry.
Pitch is another name for the frequency of sound waves . . . that is, how close the waves are together. Pitch is a term usually used in terms of music.
For light waves the term is transparent, but there are probably other terms in the case of sound waves, water waves, seismic waves, etc.Another term used is the medium, but electromagnetic radiation is an exception as it needs to medium to propagate it.
It depends on how you define "sound". If you define "sound" as "pressure waves", then yes it exists outside your mind. (Arguably, it exists outside your mind no matter how it's defined... in my mind, for example. If your philosophy teacher disagrees, accuse him of being a solipsist; that should start a discussion that will derail your class for the rest of the period.)
A specific instance of sound waves at a particular moment in time is often referred to as a sound wave snapshot. This term highlights the temporary nature of sound waves as they travel through a medium such as air or water.
Doppler effect is the term that describes the apparent change in frequency of sound waves as a source of sound moves relative to an observer. This phenomenon causes the pitch of the sound to appear higher as the source approaches the observer and lower as it moves away.