
2006-01-30, 18:16
|
 |
Senior Metalhead
|
|
Join Date: Oct 2004
Location: Jacksonville, FL
Posts: 147
|
|
Quote:
|
Originally Posted by johnmansley
Volume - or loudness - is subjective and related to three things:
1. The energy of the vibrating source.
2. The condition of the medium through which it propagates.
3. The distance involved.
The energy of a soundwave is related to its amplitude such that soundwaves with large amplitudes possess higher energy than those with smaller amplitudes.
Now, constructive interference occurs when the peaks or troughs of two distinct waves travelling in opposite directions coincide. The net effect of such an occurrence is that the amplitude of the newly combined wave is twice that of the original waves, resulting in greater energy.
|
Constructive interference does not necessarily have two do with two waves traveling in opposite directions. The peaks don't even necessarily have to even line up, since all interference is is a superposition of different waveforms.
You can have two different waveforms of different frequencies construct or destruct. For my job, I deal with seismic wave propogation in earth, and we have cases where we will have one waveform accelerate another, both having different frequencies, and they will interfere. Our goal is to time these things so they DESTRUCT, to reduce vibrations (to make the Army Corps of Engineers happy!).
Although I am very impressed at how much you guys know about this stuff!
|

2006-01-30, 21:42
|
 |
I am a tax on the world..
Forum Leader
|
|
Join Date: Mar 2002
Location: pizza with a shit on it!
Posts: 7,993
|
|
Bad-fucking-ass man,  .
LambOfsatan......Yes, exactly. If you saw my post above yours, you'll see that I said I hope you don't get into that idea, because that's wayyyy too rhetorical and off topic to discuss in this thread.
__________________
Man, I get real sweaty after I wack my dong. Yeah, cause I headbang while I do, and I can't really "Jump" (haha ) like VanHalen in a dorm room, so I just walk back and forth....haha a couple days ago I was jumping up and down on my bed, with my pants down and my roommate came in when I wasn't looking, hahaha.
 
This is my band's page
http://www.myspace.com/ferocitydentontx
|

2006-01-31, 05:31
|
 |
Schrodinger's Cat
Forum Leader
|
|
Join Date: Dec 2003
Location: Liverpool, England
Posts: 5,957
|
|
Quote:
|
Originally Posted by lamb_of_satan
Ok but if i told you to explain what colour is to a person who is blind from birth how would you go about (even if that person knows all that there is to know about the physical properties of light...but has never seen colour)
similarly how would you expalin sound (or in this case loudness) to a deaf person
(we know what sound is; we know how it works in the physical world (through vibrations or pressure waves). We know the mechanics of sound and it's properties.)......but knowing these is not enough ....there is that one variable missing that will give us all the knowledge about the qualia being discussed
Untill we find it (which i hope we dont) i guess humans are better off with measurements made dependent on "general" human experience....
|
This is veering towards the philosophy of perception and I don't really think that this is necessary given the context of the thread. Maybe make a Philosophy of Hearing thread or something - I think it would have a place in the Theory Forum and would garner a slightly different response to that in this thread since loudness and intensity would not be the issue.
Perception does have importance in physics - the act of making measurements and observations in Quantum Mechanics, for example - but for the purposes of the physics of sound wave propagation, it's not really an issue beyond philosophy. Thanks for your input, though.
Jaxadam: sounds like you've got an interesting job there. I realise that my definitions are very much simplified since my education in the subject only extends to one module when I was 17 or 18. Of course, more advanced knowledge is always very much welcomed. Cheers!
__________________
Album of the day:
Winterfylleth - The Thredony of Triumph
|

2006-01-31, 09:10
|
 |
Senior Metalhead
|
|
Join Date: Oct 2004
Location: Jacksonville, FL
Posts: 147
|
|
Quote:
|
Originally Posted by johnmansley
Jaxadam: sounds like you've got an interesting job there. I realise that my definitions are very much simplified since my education in the subject only extends to one module when I was 17 or 18. Of course, more advanced knowledge is always very much welcomed. Cheers!
|
Yeah, I've got a very interesting job, believe it or not. I work for a specialty explosives company that blow things up all around the world; buildings, bridges, you name it. My job is to make sure the vibrations from the blasts don't damage surrounding structures.
You've definitely got your head on your shoulders if you know these things by only taking one module of a physics class. I majored in physics in college, and it took me a very long time to understand what was going on! I'm getting ready to work on my PhD, and I still feel like I don't have a clue sometimes! But you know what they say, PhD just stands for "piled higher and deeper..."
|

2006-01-31, 09:51
|
 |
Schrodinger's Cat
Forum Leader
|
|
Join Date: Dec 2003
Location: Liverpool, England
Posts: 5,957
|
|
|
Haha!
__________________
Album of the day:
Winterfylleth - The Thredony of Triumph
|

2006-02-01, 03:30
|
|
Senior Metalhead
|
|
Join Date: Oct 2005
Posts: 247
|
|
|
Good luck with ur PhD man
Yeah anyway lets close this post (johnmansley)
|
| Thread Tools |
Search this Thread |
|
|
|
| Rate This Thread |
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -5. The time now is 07:25.
|