Hello everyone! :-)(adsbygoogle = window.adsbygoogle || []).push({});

Actually I'm starting to understand acoustics physics and I figured actually out about this equation:

$$\frac{\partial^2\psi}{\partial t^2}=c^2 \nabla^2 \psi$$

which describes practically about pressure and propagation speed into space and time. I know also this equation describes practically also the decrement of sound intensity in time from a source to a destination...if we would talk about particle pressure it's decrement of pressure in space by inverse square-law.

So knowing, for spherical waves , the sound intensity in a certain point of time is:

$$I = \frac{W}{4\pi r^2}$$

and supposing to have a sound diffusor with max power output of 150W and knowing human ear voice range audibility is about 40dB-60dB and supposing I want to haveI = 50dBat the time entering in my ear so how I can calculate which power output I have to set the sound diffusor to obtain that intensityII said before?

Could you help me with this little example so I can understand and study all steps to obtain all values in all situations?

Thanks in advance to all!

Cheers,

Nunzio Luigi

<Moderator's note: LaTeX fixed. Please see https://www.physicsforums.com/help/latexhelp/>

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# I About acoustics physics -- The Wave Equation and diminishing sound intensity

Have something to add?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**