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| {{multiple issues|
| | Greetings! I am Myrtle Shroyer. Puerto Rico is exactly where he and his wife live. Bookkeeping is my profession. Doing ceramics is what my family members and I enjoy.<br><br>my blog post healthy food delivery ([http://Bit.do/Lu9u my latest blog post]) |
| {{Notability|date=October 2008}}
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| {{Unreferenced|date=October 2008}}
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| }}
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| {{Sound measurements}}
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| The '''sound energy density''' or sound density (symbol ''E'' or ''w'') is an adequate measure to describe the sound field at a given point as a sound energy value. The letter "lower case w" sign <math>w</math> is easily mixed with the sign <math>\omega</math> (omega), therefore we choose the letter ''E''.
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| In opposite to the [[sound intensity]] ''I'', which gives the sound power per area ''A'', the sound energy density ''E'' (also: sound density) describes the time medium value of the sound energy per volume unit; it gives information about the sound energy which is at a defined place in the room.
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| The sound energy density ''E'' (or ''w'') for an even-proceeding [[sound wave]] is:
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| :<math>
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| E = \frac{I}{c}
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| </math>,
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| where ''I'' is the sound intensity in W/m<sup>2</sup> and ''c'' is the [[sound speed]] in m/s.<br> | |
| The sound energy density is given in J/m<sup>3</sup>, where the joule J = W·s = N·m.<br>
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| You will find also W·s/m<sup>3</sup> or N·m/m<sup>3</sup>.<br>
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| The unit of measurement for sound energy density is N/m<sup>2</sup>, also known as [[pascal (unit)|pascal]]s, the same as the units of sound pressure.
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| The terms instantaneous energy density, maximum energy density, and peak energy density have meanings analogous to the related terms used for sound pressure. In speaking of average energy density, it is necessary to distinguish between the space average (at a given instant) and the time average (at a given point).
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| More formulas for sound energy density for even proceeding sound waves:
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| :<math>
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| E = \xi^2 \cdot \omega^2 \cdot \rho = v^2 \cdot \rho = \frac{a^2 \cdot \rho}{\omega^2} = \frac{p^2}{Z \cdot c} = \frac{I}{c} = \frac{P_{ac}}{c \cdot A} = \frac{I}{f \cdot \lambda}
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| </math>
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| where:
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| {|class="wikitable"
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| ! Symbol !! Units !! Meaning
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| |-
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| ! ''p''
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| | [[pascal (unit)|pascal]]s || [[sound pressure]]
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| |-
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| ! ''f''
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| | [[hertz]] || [[frequency]]
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| |-
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| ! ''ξ''
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| | m, meters || [[particle displacement]]
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| |-
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| ! ''c''
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| | m/[[second|s]] || [[speed of sound]]
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| |-
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| ! ''v''
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| | [[Meter per second|m/s]] || [[particle velocity]]
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| |-
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| ! ''<math>\omega</math>'' = 2 · <math>\pi</math> · ''f''
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| | [[radian]]s/[[second|s]] || [[angular frequency]]
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| |-
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| ! ''ρ''
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| | [[kilogram|kg]]/m<sup>3</sup> || [[density of air]]
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| |-
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| ! ''Z = c · ρ''
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| | [[newton (unit)|N]]·[[second|s]]/m³ || [[acoustic impedance]]
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| |-
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| ! ''a''
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| | m/[[second|s]]² || [[particle acceleration]]
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| |-
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| ! ''I''
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| | [[Watt|W]]/m² || [[sound intensity]]
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| |-
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| ! ''E''
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| | [[Watt|W]]·[[second|s]]/m³ || sound energy density
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| |-
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| ! ''λ''
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| | [[Metre|m]] || [[wavelength]]
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| |-
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| ! ''P''<sub>ac</sub>
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| | W, [[watt]]s || [[sound power]] or [[acoustic power]]
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| |-
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| ! ''A''
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| | m² || [[area]]
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| |}
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| For digits of the sound energy density the [[Root mean square|RMS]] value will be given.<br>
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| But you get also the [[Sound_pressure_level#Sound_pressure_level|level]] in [[Decibel|dB]]. See [[sound energy density level]].
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| == See also ==
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| *[[Particle velocity level]]
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| *[[Sound intensity level]]
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| *[[Sound energy density level]]
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| == External links ==
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| *[http://www.sengpielaudio.com/calculator-soundlevel.htm Conversion: sound intensity to sound intensity level]
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| *[http://www.sengpielaudio.com/calculator-ak-ohm.htm Ohm's law as acoustic equivalent - calculations]
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| *[http://www.sengpielaudio.com/RelationshipsOfAcousticQuantities.pdf Relationships of acoustic quantities associated with a plane progressive acoustic sound wave - pdf]
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| [[Category:Sound measurements]]
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Greetings! I am Myrtle Shroyer. Puerto Rico is exactly where he and his wife live. Bookkeeping is my profession. Doing ceramics is what my family members and I enjoy.
my blog post healthy food delivery (my latest blog post)