128 relations: Acoustic dispersion, Acoustic shadow, Acoustical oceanography, Acoustoelastic effect, Adiabatic process, Albert Beaumont Wood, American Civil War, Atmosphere (unit), Atmosphere of Earth, Audio frequency, Battle of Iuka, Bell X-1, Boltzmann constant, Bulk modulus, Celsius, Ceteris paribus, Chemical bond, Church of St Laurence, Upminster, Classical mechanics, Compressibility, Density, Derivative, Desiccant, Deuterium, Digital data, Dispersion relation, Earthquake, Elastic modulus, Elasticity (physics), Electron, Entropy, Equation of state, Flight instruments, Fluid dynamics, Frequency, Gas, Gas constant, Group velocity, Heat capacity, Heat capacity ratio, Helium, Hertz, Hot chocolate effect, Ideal gas, Ion, Isaac Newton, Isothermal process, Isotopes of hydrogen, Knot (unit), Kundt's tube, ..., Lapse rate, Linear elasticity, Liquid, Longitudinal wave, Mach number, Marin Mersenne, Mean free path, Microphone, Molecular mass, NASA X-43, Nitrogen, Noble gas, Node (physics), North Ockendon, Nuclear explosion, Optical fiber, Orthogonality, Oxygen, Ozone layer, P-wave, Paris inch, Parts-per notation, Pascal (unit), Per mille, Phase velocity, Pierre Gassendi, Pierre-Simon Laplace, Pipe (fluid conveyance), Pitot tube, Plasma (physics), Poisson's ratio, Polarization (waves), Pressure, Project Mogul, Proton, Rector (ecclesiastical), Refraction, Refractive index, Relativistic Euler equations, Robert Boyle, S-wave, Salinity, Second sound, Seismology, Shear modulus, SOFAR channel, Solid, Sonar, Sonic boom, Sound, Sound barrier, Sound speed gradient, Special relativity, Speed, Sponge (material), Spring (device), Standard conditions for temperature and pressure, Stiffness, Stratosphere, Supersonic speed, Taylor series, Temperature, Thermodynamic temperature, Thermodynamics, Thermosphere, Time, Transverse wave, Triangulation, Tuning fork, Ultrasound, Underwater acoustics, Upminster, Van der Waals equation, Vibration, Water, William Derham, Xenon, Young's modulus. Expand index (78 more) » « Shrink index
Acoustic dispersion is the phenomenon of a sound wave separating into its component frequencies as it passes through a material.
An acoustic shadow or sound shadow is an area through which sound waves fail to propagate, due to topographical obstructions or disruption of the waves via phenomena such as wind currents, buildings, or sound barriers.
Acoustical oceanography is the use of underwater sound to study the sea, its boundaries and its contents.
The acoustoelastic effect describes how the sound velocities (both longitudinal and shear wave velocities) of an elastic material change if subjected to an initial static stress field.
In thermodynamics, an adiabatic process is one that occurs without transfer of heat or matter between a thermodynamic system and its surroundings.
Albert Beaumont Wood DSc (1890 – 19 July 1964), better known as A B Wood, was a British physicist, known for his pioneering work in the field of underwater acoustics and sonar.
The American Civil War (also known by other names) was a war fought in the United States from 1861 to 1865.
The standard atmosphere (symbol: atm) is a unit of pressure defined as.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
An audio frequency (abbreviation: AF) or audible frequency is characterized as a periodic vibration whose frequency is audible to the average human.
The Battle of Iuka was fought on September 19, 1862, in Iuka, Mississippi, during the American Civil War.
The Bell X-1 was a rocket engine–powered aircraft, designated originally as the XS-1, and was a joint National Advisory Committee for Aeronautics–U.S. Army Air Forces–U.S. Air Force supersonic research project built by Bell Aircraft.
The Boltzmann constant, which is named after Ludwig Boltzmann, is a physical constant relating the average kinetic energy of particles in a gas with the temperature of the gas.
The bulk modulus (K or B) of a substance is a measure of how resistant to compressibility that substance is.
The Celsius scale, previously known as the centigrade scale, is a temperature scale used by the International System of Units (SI).
Ceteris paribus or caeteris paribus is a Latin phrase meaning "other things equal".
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds.
The church of St Laurence, Upminster, is the Church of England parish church in Upminster, England.
Classical mechanics describes the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars and galaxies.
In thermodynamics and fluid mechanics, compressibility (also known as the coefficient of compressibility or isothermal compressibility) is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change.
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume.
The derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value).
A desiccant is a hygroscopic substance that induces or sustains a state of dryness (desiccation) in its vicinity; it is the opposite of a humectant.
Deuterium (or hydrogen-2, symbol or, also known as heavy hydrogen) is one of two stable isotopes of hydrogen (the other being protium, or hydrogen-1).
Digital data, in information theory and information systems, is the discrete, discontinuous representation of information or works.
In physical sciences and electrical engineering, dispersion relations describe the effect of dispersion in a medium on the properties of a wave traveling within that medium.
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves.
An elastic modulus (also known as modulus of elasticity) is a quantity that measures an object or substance's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it.
In physics, elasticity (from Greek ἐλαστός "ductible") is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed.
The electron is a subatomic particle, symbol or, whose electric charge is negative one elementary charge.
In statistical mechanics, entropy is an extensive property of a thermodynamic system.
In physics and thermodynamics, an equation of state is a thermodynamic equation relating state variables which describe the state of matter under a given set of physical conditions, such as pressure, volume, temperature (PVT), or internal energy.
Flight instruments are the instruments in the cockpit of an aircraft that provide the pilot with information about the flight situation of that aircraft, such as altitude, airspeed and direction.
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids - liquids and gases.
Frequency is the number of occurrences of a repeating event per unit of time.
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
The gas constant is also known as the molar, universal, or ideal gas constant, denoted by the symbol or and is equivalent to the Boltzmann constant, but expressed in units of energy per temperature increment per mole, i.e. the pressure-volume product, rather than energy per temperature increment per particle.
The group velocity of a wave is the velocity with which the overall shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space.
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
In thermal physics and thermodynamics, the heat capacity ratio or adiabatic index or ratio of specific heats or Poisson constant, is the ratio of the heat capacity at constant pressure to heat capacity at constant volume.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.
The hot chocolate effect, also known as the allassonic effect, is a phenomenon of wave mechanics first documented in 1982 by Frank Crawford, where the pitch heard from tapping a cup of hot liquid rises after the addition of a soluble powder.
An ideal gas is a theoretical gas composed of many randomly moving point particles whose only interactions are perfectly elastic collisions.
An ion is an atom or molecule that has a non-zero net electrical charge (its total number of electrons is not equal to its total number of protons).
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, astronomer, theologian, author and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time, and a key figure in the scientific revolution.
An isothermal process is a change of a system, in which the temperature remains constant: ΔT.
Hydrogen (1H) has three naturally occurring isotopes, sometimes denoted 1H, 2H, and 3H.
The knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h (approximately 1.15078 mph).
Kundt's tube is an experimental acoustical apparatus invented in 1866 by German physicist August Kundt for the measurement of the speed of sound in a gas or a solid rod.
Lapse rate is the rate at which Earth's atmospheric temperature decreases with an increase in altitude, or increases with the decrease in altitude.
Linear elasticity is the mathematical study of how solid objects deform and become internally stressed due to prescribed loading conditions.
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure.
Longitudinal waves are waves in which the displacement of the medium is in the same direction as, or the opposite direction to, the direction of propagation of the wave.
In fluid dynamics, the Mach number (M or Ma) is a dimensionless quantity representing the ratio of flow velocity past a boundary to the local speed of sound.
Marin Mersenne, Marin Mersennus or le Père Mersenne (8 September 1588 – 1 September 1648) was a French polymath, whose works touched a wide variety of fields.
In physics, the mean free path is the average distance traveled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions), which modify its direction or energy or other particle properties.
A microphone, colloquially nicknamed mic or mike, is a transducer that converts sound into an electrical signal.
Relative Molecular mass or molecular weight is the mass of a molecule.
The X-43 was an experimental unmanned hypersonic aircraft with multiple planned scale variations meant to test various aspects of hypersonic flight.
Nitrogen is a chemical element with symbol N and atomic number 7.
The noble gases (historically also the inert gases) make up a group of chemical elements with similar properties; under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity.
A node is a point along a standing wave where the wave has minimum amplitude.
North Ockendon is the easternmost and most outlying settlement of Greater London, England and part of the London Borough of Havering.
A nuclear explosion is an explosion that occurs as a result of the rapid release of energy from a high-speed nuclear reaction.
An optical fiber or optical fibre is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
In mathematics, orthogonality is the generalization of the notion of perpendicularity to the linear algebra of bilinear forms.
Oxygen is a chemical element with symbol O and atomic number 8.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation.
A P-wave is one of the two main types of elastic body waves, called seismic waves in seismology.
The Paris inch or pouce is an archaic unit of length that, among other uses, was common for giving the measurement of lenses.
In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
A per milleCambridge Dictionary Online.
The phase velocity of a wave is the rate at which the phase of the wave propagates in space.
Pierre Gassendi (also Pierre Gassend, Petrus Gassendi; 22 January 1592 – 24 October 1655) was a French philosopher, priest, astronomer, and mathematician.
Pierre-Simon, marquis de Laplace (23 March 1749 – 5 March 1827) was a French scholar whose work was important to the development of mathematics, statistics, physics and astronomy.
A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases (fluids), slurries, powders and masses of small solids.
A Pitot tube, also known as Pitot probe, is a flow measurement device used to measure fluid flow velocity.
Plasma (Henry George Liddell, Robert Scott, A Greek English Lexicon, on Perseus) is one of the four fundamental states of matter, and was first described by chemist Irving Langmuir in the 1920s.
Poisson's ratio, denoted by the Greek letter 'nu', \nu, and named after Siméon Poisson, is the negative of the ratio of (signed) transverse strain to (signed) axial strain.
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.
Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.
Project Mogul (sometimes referred to as Operation Mogul) was a top secret project by the US Army Air Forces involving microphones flown on high-altitude balloons, whose primary purpose was long-distance detection of sound waves generated by Soviet atomic bomb tests.
A rector is, in an ecclesiastical sense, a cleric who functions as an administrative leader in some Christian denominations.
Refraction is the change in direction of wave propagation due to a change in its transmission medium.
In optics, the refractive index or index of refraction of a material is a dimensionless number that describes how light propagates through that medium.
In fluid mechanics and astrophysics, the relativistic Euler equations are a generalization of the Euler equations that account for the effects of special relativity.
Robert Boyle (25 January 1627 – 31 December 1691) was an Anglo-Irish natural philosopher, chemist, physicist, and inventor.
In seismology, S-waves, secondary waves, or shear waves (sometimes called an elastic S-wave) are a type of elastic wave, and are one of the two main types of elastic body waves, so named because they move through the body of an object, unlike surface waves.
Salinity is the saltiness or amount of salt dissolved in a body of water (see also soil salinity).
Second sound is a quantum mechanical phenomenon in which heat transfer occurs by wave-like motion, rather than by the more usual mechanism of diffusion.
Seismology (from Ancient Greek σεισμός (seismós) meaning "earthquake" and -λογία (-logía) meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies.
In materials science, shear modulus or modulus of rigidity, denoted by G, or sometimes S or μ, is defined as the ratio of shear stress to the shear strain: where The derived SI unit of shear modulus is the pascal (Pa), although it is usually expressed in gigapascals (GPa) or in thousands of pounds per square inch (ksi).
Sound speed as a function of depth at a position north of Hawaii in the Pacific Ocean derived from the 2005 World Ocean Atlas. The SOFAR channel axis is at ca. 750-m depth The SOFAR channel (short for Sound Fixing and Ranging channel), or deep sound channel (DSC), is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum.
Solid is one of the four fundamental states of matter (the others being liquid, gas, and plasma).
Sonar (originally an acronym for SOund Navigation And Ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels.
A sonic boom is the sound associated with the shock waves created whenever an object traveling through the air travels faster than the speed of sound.
In physics, sound is a vibration that typically propagates as an audible wave of pressure, through a transmission medium such as a gas, liquid or solid.
The sound barrier or sonic barrier is a popular term for the sudden increase in aerodynamic drag and other effects experienced by an aircraft or other object when it approaches supersonic speed.
In acoustics, the sound speed gradient is the rate of change of the speed of sound with distance, for example with depth in the ocean, or height in the Earth's atmosphere.
In physics, special relativity (SR, also known as the special theory of relativity or STR) is the generally accepted and experimentally well-confirmed physical theory regarding the relationship between space and time.
In everyday use and in kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.
A sponge is a tool or cleaning aid made of soft, porous material.
A spring is an elastic object that stores mechanical energy.
Standard conditions for temperature and pressure are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data.
Stiffness is the rigidity of an object — the extent to which it resists deformation in response to an applied force.
The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere.
Supersonic travel is a rate of travel of an object that exceeds the speed of sound (Mach 1).
In mathematics, a Taylor series is a representation of a function as an infinite sum of terms that are calculated from the values of the function's derivatives at a single point.
Temperature is a physical quantity expressing hot and cold.
Thermodynamic temperature is the absolute measure of temperature and is one of the principal parameters of thermodynamics.
Thermodynamics is the branch of physics concerned with heat and temperature and their relation to energy and work.
The thermosphere is the layer of the Earth's atmosphere directly above the mesosphere and below the exosphere.
Time is the indefinite continued progress of existence and events that occur in apparently irreversible succession from the past through the present to the future.
A transverse wave is a moving wave that consists of oscillations occurring perpendicular (right angled) to the direction of energy transfer (or the propagation of the wave).
In trigonometry and geometry, triangulation is the process of determining the location of a point by forming triangles to it from known points.
A tuning fork is an acoustic resonator in the form of a two-pronged fork with the prongs (tines) formed from a U-shaped bar of elastic metal (usually steel).
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing.
Underwater acoustics is the study of the propagation of sound in water and the interaction of the mechanical waves that constitute sound with the water and its boundaries.
Upminster is a suburban town in east London, England, and part of the London Borough of Havering.
The van der Waals equation (or van der Waals equation of state; named after Johannes Diderik van der Waals) is based on plausible reasons that real gases do not follow the ideal gas law.
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point.
Water is a transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms.
William Derham FRS (26 November 1657 – 5 April 1735)Smolenaars, Marja.
Xenon is a chemical element with symbol Xe and atomic number 54.
Young's modulus, also known as the elastic modulus, is a measure of the stiffness of a solid material.