Joho the Blog
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If there are multiple sources of sound around you (e.g., the various instruments in an orchestra), you can hear all of them, right? Same thing.

different wavelengths. if you throw a rock in the ocean, it still makes ripples even on the face of a 6 ft wave.

But air is a gas. Why wouldn't the tiny pressure wave made by, say, a cricket get completely scattered by the cross currents, the drafts, the breezes? It just doesn't seem plausible that I can hear a cricket 50 meters away when there's even a moderate breeze.

I am forced to conclude that sound does not work.

Sound is additive. It's your ears that are really good at filtering out the noise, sometimes. It is the old hearing one conversation across the room thing. It all falls apart when things get too loud and the ears can no longer descriminate (did I spell that right?). The microphone does not do a good a job of filtering thus you end up having to put a sock on it to eliminate wind noises etc.

Thanks, but it still seems implausible. If I wave my hand underwater, you won't be able to feel it ten feet away much less 50 meters away (I think). If you set up an underwater fan that creates a jet of water perpendicular to the direction in which I've shoved , that jet will certainly dissipate the underwater wave I've created, no? Air as a gas should be even worse at transmitting waves than is liquid water. So, why don't sounds dissipate almost like smoke in air?

Physics-wise, I think all of these waves, however dissipated, could still be sensed by a sensitive instrument--especially one coupled with a pattern recognition device. So...

The ear drum is a really sensitive instrument, and the brain has the means to recognize frequency relationships. The brain-mechanism does some things really well, in terms of separating out different types of sounds, mapping their source-location in space, and connecting a series of sounds in time.

(And, if you're a cat or a bat, etc., you get additional triangulation abilities relative to space and time.)

With your underwater example, on one hand, you are comparing the ear drum's sensitivity to human skin/touch. Then, there is the brain issue--what our brains do with sound vs touch. Maybe your skin can sense tiny pertubations in the waves, but your brain isn't designed to "read" them.

It's possible to change the "focus" of your hearing. Mostly, we do it unconsciously. But, you can train yourself to better hear quieter sounds / better filter out louder ones.

"Sound is a wave moving through a medium, right?"

Wrong. Sound is what the brain and ear pick up from pressure differences in time around us. A wave moving through a medium is called a wave.

"How can we hear anything in a breeze except the breeze?"

I can hear the breeze. I cannot hear many of the sound sources that I would have heard without the breeze, because the breeze blows away the air particles that would otherwise have caused the sensation of sound.

"Different wavelengths."

What he said.

"I am forced to conclude that sound does not work."

That argument won't even work for a solipsist.

Sound IS affected by the wind. But sound moves so much faster than the wind that the effect is not usually noticable.

A good place to notice this is around the summit of Mt. Washington in New Hampshire. When the cog railroad steam engine arrives at the top, and the wind is strong and changing direction, the effect is very noticable.

You can also hear it pretty well at small airports.

If the wind were moving at the speed of sound, you probably wouldn't hear anything. You probably would be blown out of your socks too, but that's beside the point.

As a medium, air has elasticity, and the efficiency of the transmission of acoustic energy is a function of the medium's elasticity. As far as the speed of the breeze is concerned, it contributes a miniscule quantity to the net vector sum of the acoustic waves reaching your ear drum.

Air moving at or near the speed of sound is being compressed and heated, which alters its bulk modulus.

Here's a bit of trivia for you: When using active sonar to search for a submarine, the acoustic energy is not reflected much by the steel hull of the submarine, which has a bulk modulus closer to that of seawater than to air. Instead, the energy is reflected by the air inside the submarine's hull, which has a much lower bulk modulus and is a much less efficient medium, more more "opaque" to sound in water.

Here's a link: http://www.newton.dep.anl.gov/askasci/phy00/phy00999.htm

I used to know this stuff, but it's been a few decades. I may have a detail wrong here or there, but as far as acoustic energy is concerned, the wind is pretty much standing still.

Dave Rogers beat me to much of what I was going to say (my daughter did this stuff in high school physics last year, so it's relatively fresh).

For a fun experiment to demonstrate how a fast breeze does muck up sound, try speaking into, and around a fan to see what happens when the fan, the speaker and the listener are in different relative positions.

Compared to the speed of sound the movement of the air is relatively slow.
Every molecule touches upon its neighbour and all together they float with the wind.
The sound-wave going through the medium is much, much faster.

The molecules stay at their place while the WAVE is passed on from molecule to molecule.

Imagine the famous model of ping-pong balls that stay at one place, move upside down and are interconnected with springs.
If you turn the handle on one end the first balls moves up and the wave moves through the whole array.

Not the right example, but here is a gif animation of a longitudal wave, but it works:
http://www.glenbrook.k12.il.us/gbssci/phys/mmedia/waves/lw.html

Imagine the whole gif-anim being a slow moving train (the moving medium) - leaving a station.
The speed of sound is so fast compared to the medium (the train) that the sound has moved through the whole train while the train has just moved a few inches.
So if you stand on the platform with the train leaving the station a sound from the first car will have moved through the whole train in a second.
The speed of sound being 331m/sec the train 5m/sec.
Hope that makes sense.