h a l f b a k e r yProfessional croissant on closed course. Do not attempt.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
|
Sine waves are easy to generate. Audio takes very little energy to create though, and produces very little energy. Sonic cannons are only in the movies. |
|
|
A laser is intense because not so much because all the light is a single frequency, but because all the lightwaves in the beam are synchronized. If you consider a single wave as rising to a maximum and then decreasing to a minimum, well, all the waves in laser light do exactly the same at the same time. In ordinary light some waves rise to a max while others decrease to a minimum, which causes them to partly cancel-out each other, with respect to detecting intensity. |
|
|
For sound waves and this Idea, you would want to duplicate that key aspect of laser light. Note that it could be possible, provided that you plan on using "phonons" moreso than ordinary sound waves. They spread out less as they traverse distance. |
|
|
I am wondeing if it is possible for waves to be in-phase all the time, if they are of different freuqncies. My understanding was that it is not possible. My guess is that, at some places, they will be inphase and at some places, they will be out-of phase. |
|
|
This is easy enough to test with a bass guitar and a clean, powerful amp. I specify bass because bass notes travel much further, through much thicker material. |
|
|
It is theorized that, before the invention of the ship propeller and the cavitation it caused, a whale's song could travel almost all the way around the world. |
|
|
Phonons, that is a beautiful word. |
|
|
Bass guitar would generate many frequncies. I think simple sine wave oscillator or sound card would be great. |
|
|
If you have an adapter to connect your laptop to the bass amp, yes. Audacity can generate any sine wave and it is free. |
|
|
How fast and how small can vortex rings be? If you
could generate them at, say 400Hz, would you not
have a targettable sonic gun? |
|
|
I read something in a Jane's quarterly about micro-vortex
rings
generated underwater using a focused hydrophone array. I
can't link to it (even if I found it) because Jane's online
access is sealed tighter than a Swiss bank, but if anyone is
interested I'll try to dig up my hard copy. |
|
|
Please do. As I indicated earlier, I always thought sonic guns to be the province of science fiction and movies. I'd love to be proven wrong in this case. |
|
|
There is a hard upper limit to the intensity of sound,
reached when the rarifcation (sp?) of the sound wave
approaches vacuum. The advantage of a mono-frequency
wave is that it will do so along its length, whereas a multi-
frequency wave would only do so where/if the waves all
reached peak or valley at the same time. |
|
|
This isn't to say that sonic weapons are impossible, but
they're a lot more likely on jupiter than earth. |
|
|
// As I indicated earlier, I always thought sonic guns to be
the province of science fiction and movies. // |
|
|
As far as we (the informed public) know, they definitely
are. DARPA abandoned researching the offensive
applications of sonic projection in the 1970s. This device
(which
was in proto-development stages at the time of the article)
had something to do with spoofing SONAR by altering
planar(?) layers in a submarine environment; something
like supercavitating decoy countermeasures, but sneakier. I
was just
contributing to [MaxB]'s query about high-frequency vortex
rings. I'll try to dig up the quarterly, but it was from '08 or
'09, so if any other Jane's subscribers know the blurb I'm
talking about and have more ducks in a row than [The
Alterother], feel free to cite it before me. |
|
|
Typical (link) vortex ring guns seem to be shooting out only one ring at a time. Using sound to do that, at say 400 Hz would mean there 400 rings shot per second. |
|
|
See [link] for a technology that uses a modulated ultrasonic beam to deliver audio in a narrow beam. |
|
|
That first link slays me. "I'll huff and I'll puff..." |
|
|
I wonder if there is a way to create a vortex ring which would shrink in diameter as it travelled. It wouldn't be a sound laser but it would pack more whallop if it converged at a target. |
|
|
...and [link] ya just gotta see. |
|
|
If it were to shrink in diameter, wouldn't it also have to
increase in wavelength? |
|
|
Question: a vortex ring rotates (ie, there is
circulation around small-circumference of the torus.
It also travels. Is the direction of rotation always
coupled to the direction of travel? |
|
|
Answer: Yes, the inner (smaller radius) travels in the direction of propagation, and the outer (larger radius) is held back by its larger mass. |
|
|
Crickets may converse by means of vortex rings [link.] |
|
|
God, this is why I so love the combination of HB and Google! |
|
|
I can't find it. Stuffed inna box someplace, no doubt. It was
off-topic anyway. |
|
|
In Science Fiction, lasers already make sound,
something akin to 'pew-pew-pew'... |
|
|
The phaser sound in Star Trek: The Next Generation is my all-time favorite weapon sound. But the sound alone didn't do any damage unfortunately... |
|
|
Didn't the hero in "Steel" have a sonic cannon? |
|
|
As does Cyborg of the Teen Titans (though I believe the
two characters are loosely based on one another). |
|
|
No, the original Cyborg was a totally different character. Please don't ask me how I know this, because I read only maybe seven comic books in my whole life, but I remember a half-man, half-robot they called Cyborg. Kind of like Bionic Man. |
|
|
You have to admit, there's a strong resemblance between
the two, even in their original forms (pre-TV series). Also,
there have been at least three different Cyborgs in various
comic book series, and more than one Steel as well. The
names are just too generic to only be used once. |
|
| |