A report on Acoustics

Lindsay's Wheel of Acoustics, which shows fields within acoustics
The fundamental and the first 6 overtones of a vibrating string. The earliest records of the study of this phenomenon are attributed to the philosopher Pythagoras in the 6th century BC.
Principles of acoustics have been applied since ancient times: a Roman theatre in the city of Amman
Spectrogram of a young girl saying "oh, no"
An inexpensive low fidelity 3.5 inch driver, typically found in small radios
St. Michael's Cave
Symphony Hall, Boston, where auditorium acoustics began
The primary auditory cortex, one of the main areas associated with superior pitch resolution
Ultrasound image of a fetus in the womb, viewed at 12 weeks of pregnancy (bidimensional-scan)

Branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound.

- Acoustics
Lindsay's Wheel of Acoustics, which shows fields within acoustics

28 related topics with Alpha

Overall

A drum produces sound via a vibrating membrane

Sound

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Vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.

Vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.

A drum produces sound via a vibrating membrane
Spherical compression (longitudinal) waves
A 'pressure over time' graph of a 20 ms recording of a clarinet tone demonstrates the two fundamental elements of sound: Pressure and Time.
Sounds can be represented as a mixture of their component Sinusoidal waves of different frequencies. The bottom waves have higher frequencies than those above. The horizontal axis represents time.
U.S. Navy F/A-18 approaching the speed of sound. The white halo is formed by condensed water droplets thought to result from a drop in air pressure around the aircraft (see Prandtl–Glauert singularity).
Figure 1. Pitch perception
Figure 2. Duration perception
Figure 3. Loudness perception
Figure 4. Timbre perception
Approximate frequency ranges corresponding to ultrasound, with rough guide of some applications

A scientist who works in the field of acoustics is an acoustician, while someone working in the field of acoustical engineering may be called an acoustical engineer.

The transparent baffles inside this auditorium were installed to optimise sound projection and reproduction, key factors in acoustical engineering.

Acoustical engineering

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Branch of engineering dealing with sound and vibration.

Branch of engineering dealing with sound and vibration.

The transparent baffles inside this auditorium were installed to optimise sound projection and reproduction, key factors in acoustical engineering.
Disney's Concert Hall was meticulously designed for superior acoustical qualities.
Ceiling of Culture Palace (Tel Aviv) concert hall is covered with perforated metal panels
At outdoor concerts like Woodstock, acoustic analysis is critical to creating the best experience for the audience and the performers.
Ultrasound image of a fetus in the womb, viewed at 12 weeks of pregnancy (bidimensional-scan)

It includes the application of acoustics, the science of sound and vibration, in technology.

Ultrasound image (sonogram) of a fetus in the womb, viewed at 12 weeks of pregnancy (bidimensional scan)

Ultrasound

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Sound waves with frequencies higher than the upper audible limit of human hearing.

Sound waves with frequencies higher than the upper audible limit of human hearing.

Ultrasound image (sonogram) of a fetus in the womb, viewed at 12 weeks of pregnancy (bidimensional scan)
An ultrasonic examination
Fetal ultrasound
Galton whistle, one of the first devices to produce ultrasound
Approximate frequency ranges corresponding to ultrasound, with rough guide of some applications
A medical ultrasound result on a piece of paper
Bats use ultrasounds to navigate in the darkness.
A dog whistle, a whistle which emits sound in the ultrasonic range, used to train dogs and other animals
Principle of flaw detection with ultrasound. A void in the solid material reflects some energy back to the transducer, which is detected and displayed.
Non-destructive testing of a swing shaft showing spline cracking
Principle of an active sonar
Sonogram of a fetus at 14 weeks (profile)
Head of a fetus, aged 29 weeks, in a "3D ultrasound"
Schematic of bench and industrial-scale ultrasonic liquid processors

Acoustics, the science of sound, starts as far back as Pythagoras in the 6th century BC, who wrote on the mathematical properties of stringed instruments.

Broca's and Wernicke's areas

Speech

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Human vocal communication using language.

Human vocal communication using language.

Broca's and Wernicke's areas

Speech is the subject of study for linguistics, cognitive science, communication studies, psychology, computer science, speech pathology, otolaryngology, and acoustics.

Various examples of physical phenomena

Physics

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Natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.

Natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.

Various examples of physical phenomena
Ancient Egyptian astronomy is evident in monuments like the ceiling of Senemut's tomb from the Eighteenth Dynasty of Egypt.
Ibn al-Haytham (c. 965–c. 1040), Book of Optics Book I, [6.85], [6.86]. Book II, [3.80] describes his camera obscura experiments.
The basic way a pinhole camera works
Galileo Galilei showed a modern appreciation for the proper relationship between mathematics, theoretical physics, and experimental physics.
Sir Isaac Newton (1643–1727), whose laws of motion and universal gravitation were major milestones in classical physics
Max Planck (1858–1947), the originator of the theory of quantum mechanics
Albert Einstein (1879–1955), whose work on the photoelectric effect and the theory of relativity led to a revolution in 20th century physics
The basic domains of physics
Solvay Conference of 1927, with prominent physicists such as Albert Einstein, Werner Heisenberg, Max Planck, Hendrik Lorentz, Niels Bohr, Marie Curie, Erwin Schrödinger and Paul Dirac
This parabola-shaped lava flow illustrates the application of mathematics in physics—in this case, Galileo's law of falling bodies.
Mathematics and ontology are used in physics. Physics is used in chemistry and cosmology.
The distinction between mathematics and physics is clear-cut, but not always obvious, especially in mathematical physics.
Classical physics implemented in an acoustic engineering model of sound reflecting from an acoustic diffuser
Archimedes' screw, a simple machine for lifting
Experiment using a laser
The astronaut and Earth are both in free fall.
Lightning is an electric current.
Physics involves modeling the natural world with theory, usually quantitative. Here, the path of a particle is modeled with the mathematics of calculus to explain its behavior: the purview of the branch of physics known as mechanics.
A simulated event in the CMS detector of the Large Hadron Collider, featuring a possible appearance of the Higgs boson.
Velocity-distribution data of a gas of rubidium atoms, confirming the discovery of a new phase of matter, the Bose–Einstein condensate
The deepest visible-light image of the universe, the Hubble Ultra-Deep Field
Feynman diagram signed by R. P. Feynman.
A typical phenomenon described by physics: a magnet levitating above a superconductor demonstrates the Meissner effect.

Classical physics includes the traditional branches and topics that were recognised and well-developed before the beginning of the 20th century—classical mechanics, acoustics, optics, thermodynamics, and electromagnetism.

The reflection of Mount Hood in Mirror Lake.

Reflection (physics)

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Change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.

Change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.

The reflection of Mount Hood in Mirror Lake.
Diagram of specular reflection
Refraction of light at the interface between two media.
An example of the law of reflection
General scattering mechanism which gives diffuse reflection by a solid surface
Working principle of a corner reflector
Multiple reflections in two plane mirrors at a 60° angle.
Sound diffusion panel for high frequencies

In acoustics, reflection causes echoes and is used in sonar.

Robert Bruce Lindsay

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Robert Bruce Lindsay (1 January 1900 – 2 March 1985) was an American physicist and physics professor, known for his prolific authorship of physics books in acoustics, and historical and philosophical analyses of physics.

The nodes of a vibrating string are harmonics.

Harmonic

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Wave with a frequency that is a positive integer multiple of the fundamental frequency, the frequency of the original periodic signal, such as a sinusoidal wave.

Wave with a frequency that is a positive integer multiple of the fundamental frequency, the frequency of the original periodic signal, such as a sinusoidal wave.

The nodes of a vibrating string are harmonics.
Two different notations of natural harmonics on the cello. First as sounded (more common), then as fingered (easier to sightread).
Playing a harmonic on a string

The term is employed in various disciplines, including music, physics, acoustics, electronic power transmission, radio technology, and other fields.

Marin Mersenne

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French polymath whose works touched a wide variety of fields.

French polymath whose works touched a wide variety of fields.

Tractatus mechanicus theoricus et practicus, 1644

. He also developed Mersenne's laws, which describe the harmonics of a vibrating string (such as may be found on guitars and pianos), and his seminal work on music theory, Harmonie universelle, for which he is referred to as the "father of acoustics".

Physical acoustics

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Physical acoustics is the area of acoustics and physics that studies interactions of acoustic waves with a gaseous, liquid or solid medium on macro- and micro-levels.