Shoutbox

It can be as loud as you want and it won't smash unless it is at the exact frequency of the glass. (back to the glass smashing bit)

*ajd impresses himself at his scientific knowledge

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Originally posted by saralk
iirc from a physics video you cant smash a class through noise, they put a glass in the same room as a speaker emmiting noise as loud as a concord engine and it still didnt work

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It's not the volume that makes it smash.
If you have a glass near a speaker that is emiting a sounds at the right frequency. The glass will start to vibrate, and as the volume is turned up, the glass vibrates more and more, until it cant take anymore, and it smashes.
Edit: ajd your faster than me

I think that this whole debate is funny aww well..

The glass would break, i even watched video footage of it happening! It was on the kids show 'How' on cbbc, i watched it a couple of years ago. 

the real truth about the glass: Well, in fact any frequency can break the glass, but the loud of that sound/noise should be very very very high for the most of frequencies. It should be so loud that maybe it's impossible to create that sound.

However each object (a glass in particular) has an associated frequency that is called resonancy frequency (sorry if the translation is dodgy) That is a special frequency beacuse the object, due to its form, the materials it's made in, etc..., amplifies a lot the power of the sounds with that frequency and then a little/medium loud of that sound can break the glass "easyly".

Theres a show called "Mythbusters" on the Discovery channel here and they did a similar experiment, except these people took a full Black and Decker drill and put it on the drive and spun it. Next to the drive, they created a rubbery dummy which resembled a human (like the toughness of the skin/muscle) and when the drive exploded, they showed the CD slicing into the dummy, It went in fairly depp, it was pretty cool

Episode Guide from that Episode:

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Episode 2: Cell Phone Destruction, Silicone Breasts, CD-ROM Shattering
In this episode, Jamie and Adam test several explosive theories. Can chatting on a cell phone while pumping gas cause the pump to blow up? Our mythbusters put themselves at risk so you don't have to. They also put silicone breast implants to the test at high altitude. Will they burst under pressure? Finally, we'll learn once and for all if high-speed CD-ROM players can really shatter a compact disc.

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Originally posted by toddy
i didn't find it too funny, it was my office xp cd

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blah... your license was expired, that's all....

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Originally posted by TheBlasphemer
Isn't that resonance?

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yup, resonance or resonance frequency...

There is even famous video footage of a normal powerfull wind (not storm though) that demolishes a large bridge. It happened that the wind blew at the same frequence of that suspencion bridge...

Also this, (funny, but very true): In the army they teach you to march, and each soldiers must walk in the same rithme. Everybody knows that. But, they also teach there that if you need to cross a bridge while marching, the soldiers may not march in the same rithme! But each soldiers must march slithly earlier/later then the one before him. This is because of the same thing, the marching frequency of a whole platoon marching in the same rithme could demolishe a bridge!

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Originally posted by CookieRevised
yup, resonance or resonance frequency...

There is even famous video footage of a normal powerfull wind (not storm though) that demolishes a large bridge. It happened that the wind blew at the same frequence of that suspencion bridge...

Also this, (funny, but very true): In the army they teach you to march, and each soldiers must walk in the same rithme. Everybody knows that. But, they also teach there that if you need to cross a bridge while marching, the soldiers may not march in the same rithme! But each soldiers must march slithly earlier/later then the one before him. This is because of the same thing, the marching frequency of a whole platoon marching in the same rithme could demolishe a bridge!

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Thats absolutely crazy, the wind was at the same frequency as a suspension bridge, and it was demolished... suppose its one less job for all of the townies to break

Thats stupid, how could an army destroy a bridge, does that mean, if you wanted to break a bridge, you get a load of your mates, steel capped boots, and get them to march across the bridge in unison... not that i'll try it or anything lol....



The glass broke, it was right next to a speaker, and when I say speaker, I mean like a marshall stack

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Originally posted by traxor
does that mean, if you wanted to break a bridge, you get a load of your mates, steel capped boots, and get them to march across the bridge in unison.

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yes indeed



* Tacoma Narrows Bridge Collapse (November 7, 1940):

http://en.wikipedia.org/wiki/Tacoma_Narrows_Bridge
(that of those soldiers is also mentioned there in a quick sentence)

http://www.eng.uab.edu/cee/reu_nsf99/tacoma.htm
http://www.madsci.org/posts/archives/may98/892678504.Eg.r.html
http://www.civeng.carleton.ca/Exhibits/Tacoma_Nar...DSmith/photos.html
http://www.vibrationdata.com/Tacoma.htm (<=nice still photo's of the bridge's resonance in action)
http://abel.math.harvard.edu/archive/21b_fall_03/tacoma/ (<= contains the video's.)
http://homepages.tscnet.com/rickc/tnb/ (<= collection of info, links and video's about the collapse)


* "Small" case study (and live example) of a physics teacher and his class doing the same with a small suspension bridge:
http://home.messiah.edu/~barrett/mpg/2harend.html



remember that there is nothing fake about these video's! This is pure science even how wierd it may seem...

PS: not many know this but the Millenium Bridge in London was also closed for a time because it began to sway alarmingly due to resonance.

You have way too much time on your hands.

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Originally posted by CookieRevised
Also this, (funny, but very true): In the army they teach you to march, and each soldiers must walk in the same rithme. Everybody knows that. But, they also teach there that if you need to cross a bridge while marching, the soldiers may not march in the same rithme! But each soldiers must march slithly earlier/later then the one before him. This is because of the same thing, the marching frequency of a whole platoon marching in the same rithme could demolishe a bridge!

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oh, yes! that's also true. At the end, it's all due to the same phisical effect. the resonance frequency.