Possible to break a glass if you emit a loud sound?

  • Context: High School 
  • Thread starter Thread starter Algren
  • Start date Start date
  • Tags Tags
    Break Glass Sound
Click For Summary

Discussion Overview

The discussion explores the potential effects of sound waves on physical structures, particularly focusing on the ability to break glass at its resonant frequency and the implications for human skulls. Participants examine both the theoretical and practical aspects of sound-induced damage, including concussive effects and resonant frequencies.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that sound at a resonant frequency can break glass, questioning if similar effects could apply to human skulls.
  • Others argue that while resonant frequencies may not apply to the human skull in the same way, high amplitude sound waves could cause concussive damage.
  • A participant mentions historical accounts where sound waves from artillery may have caused fatalities without visible injuries.
  • Some discuss the use of sound waves in laboratory settings to break cells, noting that the medium (air vs. liquid) affects the outcome.
  • There are suggestions about using underwater speakers to amplify sound effects on humans, though concerns about equipment durability are raised.
  • Participants express skepticism about the existence of a resonant frequency for the human skull, contrasting it with the resonant frequency of the human sphincter muscle, which is humorously noted.
  • Some participants question the feasibility of using sound as a weapon, suggesting ideas like sound-absorbing planes to mitigate effects on friendly forces.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the potential for sound to cause fatal effects on humans, with multiple competing views regarding the mechanisms and implications of sound waves on physical structures.

Contextual Notes

There are unresolved questions about the specific resonant frequencies of various human body parts and the conditions under which sound waves can cause damage. The discussion also touches on historical interpretations of sound in warfare, which may lack definitive evidence.

Algren
Messages
74
Reaction score
1
Knowing that its possible to break a glass if you emit a loud sound at its resonant frequency.

If you do the same for Human skulls, there will not only be a sound sleep, but a sound death too. Is that possible?
 
Physics news on Phys.org
As I recall, some soldiers were found killed at the battle of Gettysburg and their bodies were unmarked. It was concluded the concussion from the shells used was sufficiently intense to have killed them. As for the complication of setting up a resonance with various body structures, it apparently is not necessary if all you want is fatal effects.
 
If you have a sound wave which is of a high enough amplitude, the pressure changes changes between the high and low pressure points on the wave would in effect almost hit you like a shockwave from a bomb blast and cause concussion damage.

Infact sound is used to destroy/break cells in labs. Not sure on the exact method but basically the cells are suspended in a solution and then a high frequency sound wave is passed through the solution which causes the cells to break up. Althought this wouldn't occur in air as air doesn't conduct sound as well as a liquid would.

Prehaps if you put the person into a large swimming pool and then played your very loud sound through underwater speakers then the sound waves would propagate well enough to cause damage. Although more likely they will shake even the best of the best of speakers to bits in seconds.
 
rollcast said:
If you have a sound wave which is of a high enough amplitude, the pressure changes changes between the high and low pressure points on the wave would in effect almost hit you like a shockwave from a bomb blast and cause concussion damage.

Infact sound is used to destroy/break cells in labs. Not sure on the exact method but basically the cells are suspended in a solution and then a high frequency sound wave is passed through the solution which causes the cells to break up. Althought this wouldn't occur in air as air doesn't conduct sound as well as a liquid would.

Prehaps if you put the person into a large swimming pool and then played your very loud sound through underwater speakers then the sound waves would propagate well enough to cause damage. Although more likely they will shake even the best of the best of speakers to bits in seconds.

Some farmers used to fish by throwing dynamite into a pond stunning/killing the fish to save on worms.
 
jedishrfu said:
relating to sound death there's another interesting quirk where historians and scientists have said battles were lost due to sound not being heard or interpretted wrongly:

http://scvcamp868.webstarts.com/uploads/Acoustician_Charles_D__Ross.pdf

and on sound refraction:

http://www.kettering.edu/physics/drussell/Demos/refract/refract.html

Well interesting, and concussion damage too.

Can there be even mis-interpretation of EM waves?

and, why can't we just fly a sound-absorbing plane with a large speaker over the enemy side and shake them to bits? Along with a nullifying wave so that those waves to not hit their own base?
 
Last edited by a moderator:
Algren said:
Knowing that its possible to break a glass if you emit a loud sound at its resonant frequency.

If you do the same for Human skulls, there will not only be a sound sleep, but a sound death too. Is that possible?

Your question seems to be specifically about resonant frequencies but the answers above have all been about concussive effects which is not the same thing. As far as I know, the human skull does not have a resonant frequency the way a glass goblet or a pane of glass does. Glass in complex configurations will not (necessarily) have a resonant frequency.

The human sphincter muscle, on the other hand, DOES have a resonant frequency, which is somewhere around 6Hz for most people. SO ... although you can't likely kill anyone by getting a resonant frequency will their skull, you COULD make them mess their pants.
 
Last edited by a moderator:
phinds said:
The human sphincter muscle, on the other hand, DOES have a resonant frequency, which is somewhere around 6Hz for most people. SO ... although you can't likely kill anyone by getting a resonant frequency will their skull, you COULD make them mess their pants.

Lol, although you can check this:

http://everything2.com/index.pl?node_id=1073503

I don't know if its a joke or not.
 
Last edited by a moderator:
  • #10
phinds said:
The human sphincter muscle, on the other hand, DOES have a resonant frequency, which is somewhere around 6Hz for most people. SO ... although you can't likely kill anyone by getting a resonant frequency will their skull, you COULD make them mess their pants.

I'm very skeptical of this...
 
  • #11
Drakkith said:
I'm very skeptical of this...

I have no expertise on this, I just read about it many years ago where a physics prof did a demo in class and the bathroom became VERY crowded before the demo was over. I know this sounds a bit unlikely, I just remember that there was SOME reason, I no longer remember what, that made me take it seriously.
 
  • #12
Well, let's save that topic for another day and the Skeptics forum lol.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 31 ·
2
Replies
31
Views
5K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 18 ·
Replies
18
Views
8K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 44 ·
2
Replies
44
Views
16K
  • · Replies 3 ·
Replies
3
Views
4K