lacoustique

Acoustics is the branch of physics that studies sound, including its production, transmission, and perception. It covers the generation of sound by vibrating bodies, the propagation of sound waves through gases, liquids, and solids, and the effects of sound on living organisms and the environment. The field spans theoretical, experimental, and applied research.

Sound is a mechanical wave characterized by frequency, amplitude, and speed. In air at room temperature, sound travels about 343 meters per second, and audible frequencies range roughly from 20 Hz to 20 kHz. Properties such as wavelength (speed divided by frequency) and impedance influence propagation, reflection, refraction, diffraction, and interference.

Subfields include physical acoustics (wave propagation and material interactions), architectural acoustics (room design and sound isolation), musical acoustics (sound production in instruments and intonation), and psychoacoustics (human perception of sound). Measurements use decibels (dB) for level and hertz (Hz) for frequency; microphones, accelerometers, and specialized sensors capture data.

Applications include acoustic design of buildings to control reverberation time and speech intelligibility, noise control and environmental acoustics, and audio technology such as loudspeakers and recording equipment. Standards and models, like RT60 and acoustic impedance, guide engineering decisions and compliance.

Beyond hearing, acoustics underpins ultrasound in medicine, nondestructive testing, sonar, and undersea communication. The field employs theoretical models and numerical methods to simulate wave behavior and optimize devices, materials, and spaces for audible quality, safety, and efficiency.