fdid u know that a nulcear bomb is louder than 200 dB's. WOW [img]smile.gif[/img] also the navi has managed to break over 200 dB's under water as well? kinda crazy

Livin Loud

 

0dB HL is the quietest level a person with normal hearing can actually hear at a given frequency using pure tones.

Blah...in Edmonton right now studing this subject. At least it is snowing [img]graemlins/thumb.gif[/img] I gets a head start on winter YA! (no that was not sarcastic)

 

Actually 6dB is double acousical energy, IE double the displacement. Double power only yeilds sqrt(2) increase in excursion and therefore displacement, theoretically.

 

194 dB is the dB limit in air at 101.325 kPa and 20 degrees celsius. At the north pole on a very cold day, it would be possible to break 200dB ( no this does not mean you would be louder there, it means the density of the air would allow for more pressure difference, allowing more force to be exerted)
Submarines sonars are around 230 dB .

Although Bell's original definition of 1 dB was the threshhold of human hearing, we now define it as
10^-12 W/m^2

 

^not sure about the cold making that much of a difference...

As I recall, its virtually impossible to break 150db in open atmosphere with a conventional speaker/driver. And at over 180db or so, a wave at STP begins to shock...

Damn- thatd be loud.. [img]graemlins/headbang.gif[/img]

 

Can't remember the exact calcaulations, but it has to be below around -80 degrees celsius to break 200 dB. At this point, there is almost no moisture in the air and the ideal gas law (pv=nRt) exhibits very little deviation from van der waal's equation and the bulk modulus of air decreases.
This is under the assumption that a sound wave is a completely adiabatic process.

[ October 21, 2004, 07:49 PM: Message edited by: seege ]

 

^^^ Oh great, now my head exploded... How am I supposed to type with all this grey matter on my keyboard? I can see a time-space continuum reference on the horizon...

 

You want to try and wrap your head around something difficult to comprehend...try no longer thinking of sound propagating as waves...

 

[img]graemlins/thumb.gif[/img]

 

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