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The resonant frequency of a SAW device is directly proportional to the velocity of the wave as it travels across the surface. The velocity is mostly determined by the material upon which the SAW propagates (such as quartz, lithium niobate, or lithium tantalate, to name a few common substrates). However, the velocity is also somewhat sensitive to a number of other parameters, including the stiffness, mass, and electrical conductivity of the substrate material or any other materials with which the wave comes into contact.
SAW sensors can, in principle, be used to measure all kinds of things, including temperature, acceleration, electric field strength, etc. However, their most common use is for chemical sensors (usually gas sensors). Most SAW chemical sensors work by virtue of mass sensitivity. The surface of a SAW resonator is coated with a thin layer of material (usually some sort of polymer) which chemically absorbs the gas of interest, kind of like a sponge soaking up water. A sponge, however, will soak up all kinds of different things - water, milk, juice, whiskey - pretty much any liquid. The polymer films on SAW gas sensors, on the other hand, are usually designed to absorb very, very specific chemicals. When the sensor is exposed to the chemical, gas molecules are adsorbed onto the polymer film, where they effectively increase the mass of the film. This tiny increase in mass causes a corresponding decrease in the velocity of the SAW, which in turn causes a decrease in the resonant frequency of the device. Since frequency can be measured with extremely high precision, gases can often be detected at extremely low concentrations, easily down in the parts per billion (ppb) or even parts per trillion (ppt) range.
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The angle that the incoming wave makes is equal to the angle that the outgoing wave makes?
This statement is describing the principle of reflection, which applies to waves bouncing off a surface. According to this principle, the angle of incidence (the angle at which the incoming wave strikes the surface) is equal to the angle of reflection (the angle at which the outgoing wave leaves the surface).
What are the three different wave types?
The three different wave types are transverse waves, longitudinal waves, and surface waves. Transverse waves oscillate perpendicular to the direction of wave propagation, longitudinal waves oscillate parallel to the direction of wave propagation, and surface waves travel along the boundary between two different mediums.
What is the speed at which an acoustic wave propagates in an incompressible flow?
The speed at which an acoustic wave propagates in an incompressible flow is determined by the bulk modulus of the medium through which the wave is traveling. In an incompressible flow, the speed of sound is constant and does not change with pressure or density variations.
What is the instrument that uses the reflection of the acoustic wave called?
An instrument that uses the reflection of an acoustic wave is called an ultrasound machine. This technology is commonly used in medical imaging to create pictures of the inside of the body.
What is a small wave called?
surface wave
What has the author R O Claus written?
R. O. Claus has written: 'Analysis and acoustooptical measurements of bulk and surface acoustic wave fields' -- subject(s): Acoustic surface waves, Piezoelectric transducers, Surface acoustic wave devices, Bulk acoustic wave devices, Acoustic measurement, Ultrasonic wave transducers, Acoustooptics, Sound waves, Acousto-optics
The angle that the incoming wave makes is equal to the angle that the outgoing wave makes?
This statement is describing the principle of reflection, which applies to waves bouncing off a surface. According to this principle, the angle of incidence (the angle at which the incoming wave strikes the surface) is equal to the angle of reflection (the angle at which the outgoing wave leaves the surface).
What has the author A J Palmer written?
A. J. Palmer has written: 'Delta-k acoustic sensing of ocean surface waves' -- subject(s): Acoustic surface waves, Ocean wave power, Measurement
What is another name for surface waves?
another name for pressure wave is a P-wave EDIT: Another name for P-waves or Pressure waves are Compressional, Longitudinal, P, Dilation waves. The particle motion is in the direction of wave propagation These waves occur in Solids, Liquids, and Gases whereas Shear, transverse, S, or equivoluminal waves only occur in solids.
How touch screen works?
It can be any type viz. Resistive, Capacitive, Surface acoustic wave. But there are many sub category of above technology.
What has the author Anil Kenneth Deisingh written?
Anil Kenneth Deisingh has written: 'Detection of Escherichia coli O157: H7 and related species by acoustic wave sensor'
What type of waves are primary waves?
A primary wave is a strong vibration or wave that hits earths surface (P) and a secondary wave (S) is a wave that hits soon after but not nearly as big.
What has the author S I Hariharan written?
S. I Hariharan has written: 'Numerical solutions of acoustic wave propagation problems using Euler computations' -- subject(s): Euler's numbers, Acoustic surface waves 'Absorbing boundary conditions for exterior problems'
What are the three different wave types?
The three different wave types are transverse waves, longitudinal waves, and surface waves. Transverse waves oscillate perpendicular to the direction of wave propagation, longitudinal waves oscillate parallel to the direction of wave propagation, and surface waves travel along the boundary between two different mediums.
How can sound wave visualizations enhance our understanding of acoustic phenomena?
Sound wave visualizations can help us see the patterns and properties of sound waves, making it easier to understand complex acoustic phenomena such as frequency, amplitude, and wave interference.
What is the height of a soundwave which indicates loudness of a sound?
It's the Acoustic Definition of Amplitude.The height of the sound wave is called its amplitude.
What is the speed at which an acoustic wave propagates in an incompressible flow?
The speed at which an acoustic wave propagates in an incompressible flow is determined by the bulk modulus of the medium through which the wave is traveling. In an incompressible flow, the speed of sound is constant and does not change with pressure or density variations.
