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Anybody know about sound propagation in water? (sonar)

Started by Unknown October 20, 2014
If you were to drop a liquid contaminant into the water, would the sound refract due to the difference in speed in the new medium?
On Monday, October 20, 2014 9:13:26 PM UTC-4, gyans...@gmail.com wrote:
> If you were to drop a liquid contaminant into the water, would the sound refract due to the difference in speed in the new medium?
is there a reason to think that there would be no refraction if there is a different wavespeed? or no reflection if there is a different characteristic impedance? alls i remember is that sound is about 5x faster in water than air. it's denser (which would slow down sound) but far more incompressible than air. r b-j
On Mon, 20 Oct 2014 18:13:26 -0700, gyansorova wrote:

> If you were to drop a liquid contaminant into the water, would the sound > refract due to the difference in speed in the new medium?
I think it depends on so many things that the only possible answer is "maybe". Mostly it would depend on how much the stuff changes the refraction index of water, and how physically large the wodge of stuff was. -- www.wescottdesign.com
gyansorova@gmail.com wrote:
> If you were to drop a liquid contaminant into the water, would > the sound refract due to the difference in speed in the new medium?
Light refracts due to changes in index of refraction. For sound in liquid, speed is a function of density and compressibility. For salt water, for example, it depends on the salt concentration which changes density a lot more than compressibility. Submarine operators can hide by going to an appropriate depth where the sounds refract away from the surface. -- glen
The speed in liquids is c = sqrt(K/Sigma), where K is the compressibility 
and Sigma is the density. In destilled water for example, the speed is 
1490 m/s, which is about 4,3 higher than in air.

/ah
On Mon, 20 Oct 2014 18:13:26 -0700, gyansorova wrote:

> If you were to drop a liquid contaminant into the water, would the sound refract due to the difference in speed in the new medium?
Is this contaminant soluble in water? If so - it's going to be hard to detect unless concentration is high. Even worse, the "boundary" will be diffuse. If not soluble - will it remain in a contiguous blob, or get broken into many cells? (same problem)