Hybrid system: Difference between revisions
en>George Ponderevo →Tools: Copyedit (minor) |
en>BG19bot m WP:CHECKWIKI error fix for #61. Punctuation goes before References. Do general fixes if a problem exists. - using AWB (9876) |
||
Line 1: | Line 1: | ||
{{Sound measurements}} | |||
'''Particle displacement''' or '''displacement amplitude''' (represented in [[mathematics]] by the [[Lower case|lower-case]] [[Greek alphabet#Main table|Greek letter]] [[Xi (letter)|ξ]]) is a [[measurement]] of [[distance]] of the movement of a particle from its equilibrium position in a medium as it transmits a [[wave]].<ref> | |||
{{cite book | |||
| title = Microsensors, MEMS, and Smart Devices | |||
| author = Julian W. Gardner, V. K. Varadan, Osama O. Awadelkarim | |||
| publisher = John Wiley and Sons | |||
| year = 2001 | |||
| isbn = 978-0-471-86109-6 | |||
| pages = 321–322 | |||
| url = http://books.google.com/books?id=ht69jE9ypSwC&pg=PA321 | |||
}}</ref> | |||
In most cases this is a [[longitudinal wave]] of pressure (such as [[sound]]), but it can also be a [[transverse wave]], such as the [[oscillation|vibration]] of a taut string. In the case of a [[sound wave]] travelling through [[air]], the '''particle displacement''' is evident in the [[oscillation]]s of air [[molecule]]s with, and against, the direction in which the sound wave is travelling.<ref>{{cite book | |||
| author= Arthur Schuster | |||
| title=An Introduction to the Theory of Optics | |||
| publisher=London: Edward Arnold | |||
| year=1904 | |||
| url = http://books.google.com/books?id=Zb4KAAAAIAAJ&printsec=frontcover&dq=An+Introduction+to+the+Theory+of+Optics+By+Arthur+Schuster | |||
}} </ref> | |||
A particle of the medium undergoes displacement according to the [[particle velocity]] of the wave traveling through the medium, while the sound wave itself moves at the [[speed of sound]], equal to 343 m/s in air at 20 °C. | |||
The instantaneous particle displacement ''ξ'' for a wave is:<ref> | |||
{{cite book | |||
| author = John Eargle | |||
| authorlink = John M. Eargle | |||
| title = The Microphone Book: From mono to stereo to surround – a guide to microphone design and application | publisher = Focal Press | date = January 2005 | |||
| location = Burlington, Ma | pages = 27 | |||
| url =http://books.google.com/books?id=w8kXMVKOsY0C&pg=PA27&dq=instantaneous+particle+displacement | |||
| isbn =978-0-240-51961-6 | |||
}}</ref> | |||
:<math> | |||
\xi = \int_{t} v\, \mathrm{d}t | |||
</math> | |||
If the wave is a standing wave or a traveling wave containing a single frequency, the particle displacement is: | |||
:<math> | |||
\xi = \frac{1}{Z} \int_{t} p\, \mathrm{d}t | |||
</math> | |||
This expression for <math>\xi</math> undergoes simple harmonic oscillation, and as such is usually expressed as an [[root mean square|RMS]] time average. | |||
'''Particle displacement''' for a traveling wave containing a single frequency can be represented in terms of other measurements: | |||
:<math> | |||
\xi = \frac{v}{\omega} | |||
= \frac{p}{Z_0 \cdot \omega} | |||
= \frac{a}{\omega^2} | |||
= \frac{1}{\omega}\sqrt{\frac{I}{Z_0}} | |||
= \frac{1}{\omega}\sqrt{\frac{E}{\rho}} | |||
= \frac{1}{\omega}\sqrt{\frac{P_{ac}}{Z_0 \cdot A}} | |||
</math> | |||
where in the above equation, the quantities <math>\xi, v, a, I, E, P_{ac}</math> may be taken throughout as rms time-averages (or all as maximum values). The single frequency traveling wave has acoustic impedance equal to the characteristic impedance, <math>Z=Z_0</math>. Further representations for <math>\xi</math> can be found from the above equations using the replacement <math>\omega=2\pi{f}</math>. | |||
{| class="wikitable" | |||
! Symbol !! Units !! Meaning | |||
|- | |||
! ''ξ'' | |||
| m, meters || Particle displacement | |||
|- | |||
! ''v'' | |||
| [[Meters per second|m/s]] || [[particle velocity]] | |||
|- | |||
! ω = 2π''f'' | |||
| [[radian]]s/[[second|s]] || [[angular frequency]] | |||
|- | |||
! ''f'' | |||
| Hz, [[hertz]] || [[frequency]] | |||
|- | |||
! ''p'' | |||
| Pa, [[pascal (unit)|pascal]]s || [[sound pressure]] | |||
|- | |||
! ''Z<sub>0</sub>'' = ''c'' · ''ρ'' | |||
| [[Newton (unit)|N]]·[[second|s]]/m<sup>3</sup> || [[characteristic impedance]] | |||
|- | |||
! ''Z'' = ''p'' / ''v'' | |||
| [[Newton (unit)|N]]·[[second|s]]/m<sup>3</sup> || [[acoustic impedance]] | |||
|- | |||
! ''c'' | |||
| m/[[second|s]] || [[Speed of sound]] | |||
|- | |||
! ''ρ'' | |||
| [[Kilogram|kg]]/m<sup>3</sup> || [[Density of air]] | |||
|- | |||
! ''I'' | |||
| [[Watt|W]]/m<sup>2</sup> || [[sound intensity]] | |||
|- | |||
! ''E'' | |||
| [[Watt|W]]·[[second|s]]/m<sup>3</sup> || [[sound energy density]] | |||
|- | |||
! ''P''<sub>ac</sub> | |||
| W, [[watt]]s || [[sound power]] or [[acoustic power]] | |||
|- | |||
! ''A'' | |||
| m<sup>2</sup> || [[Area]] | |||
|- | |||
! ''a'' | |||
| m/[[second|s]]<sup>2</sup> || [[Particle acceleration]] | |||
|} | |||
== See also == | |||
* [[Wave]] | |||
* [[Sound particle]] | |||
==References and notes== | |||
{{reflist}} | |||
'''Related Reading:''' | |||
*{{cite book | author=Wood, Robert Williams | |||
| title=Physical optics | publisher=New York: The Macmillan Company | year=1914}} | |||
*{{cite book | author=Strong, John Donovan; and Hayward, Roger | |||
| title=Concepts of Classical Optics | publisher=Dover Publications | year=January 2004 | |||
| isbn= 978-0-486-43262-5 | page= }} | |||
*{{cite book | last = Barron | first = Randall F. | |||
| authorlink = | coauthors = | title = Industrial noise control and acoustics | |||
| publisher = CRC Press | date = January 2003 | |||
| location = NYC, New York | pages = 79, 82, 83, 87 | |||
| url =http://books.google.com/books?id=k1tXPl2hC-cC&pg=PA82&dq=instantaneous+particle+displacement | |||
| doi = | id = | |||
| isbn =978-0-8247-0701-9}} | |||
== External links == | |||
*[http://acoustics.open.ac.uk/802574C70048F266/%28httpAssets%29/EC0466002A53AFDD802574E200381B0C/$file/ali_tonddast_navaei_thesis.pdf Acoustic particle-image velocimetry - Development and applications] | |||
*[http://www.sengpielaudio.com/calculator-ak-ohm.htm Ohm's law as acoustic equivalent - calculations] | |||
*[http://www.sengpielaudio.com/RelationshipsOfAcousticQuantities.pdf Relationships of acoustic quantities associated with a plane progressive acoustic sound wave - pdf] | |||
[[Category:Sound measurements]] |
Revision as of 06:55, 27 January 2014
Leather Items Maker Truman from Manotick, likes to spend some time caravaning, property developers in Singapore Property New and church/church activities. Had been especially enthused after visiting Vallée de Mai Nature Reserve. Particle displacement or displacement amplitude (represented in mathematics by the lower-case Greek letter ξ) is a measurement of distance of the movement of a particle from its equilibrium position in a medium as it transmits a wave.[1] In most cases this is a longitudinal wave of pressure (such as sound), but it can also be a transverse wave, such as the vibration of a taut string. In the case of a sound wave travelling through air, the particle displacement is evident in the oscillations of air molecules with, and against, the direction in which the sound wave is travelling.[2] A particle of the medium undergoes displacement according to the particle velocity of the wave traveling through the medium, while the sound wave itself moves at the speed of sound, equal to 343 m/s in air at 20 °C.
The instantaneous particle displacement ξ for a wave is:[3]
If the wave is a standing wave or a traveling wave containing a single frequency, the particle displacement is:
This expression for undergoes simple harmonic oscillation, and as such is usually expressed as an RMS time average.
Particle displacement for a traveling wave containing a single frequency can be represented in terms of other measurements:
where in the above equation, the quantities may be taken throughout as rms time-averages (or all as maximum values). The single frequency traveling wave has acoustic impedance equal to the characteristic impedance, . Further representations for can be found from the above equations using the replacement .
Symbol | Units | Meaning |
---|---|---|
ξ | m, meters | Particle displacement |
v | m/s | particle velocity |
ω = 2πf | radians/s | angular frequency |
f | Hz, hertz | frequency |
p | Pa, pascals | sound pressure |
Z0 = c · ρ | N·s/m3 | characteristic impedance |
Z = p / v | N·s/m3 | acoustic impedance |
c | m/s | Speed of sound |
ρ | kg/m3 | Density of air |
I | W/m2 | sound intensity |
E | W·s/m3 | sound energy density |
Pac | W, watts | sound power or acoustic power |
A | m2 | Area |
a | m/s2 | Particle acceleration |
See also
References and notes
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
Related Reading:
- 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534
External links
- Acoustic particle-image velocimetry - Development and applications
- Ohm's law as acoustic equivalent - calculations
- Relationships of acoustic quantities associated with a plane progressive acoustic sound wave - pdf
- ↑
20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - ↑ 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - ↑
20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534