Slashdot Mirror
The Weird Science of Tossing Stones Into a Lake
Interoperable writes "Researchers in Spain and the Netherlands add another piece to a centuries-old puzzle in physics: the dynamics of an object falling into water. This common occurrence has a complex anatomy that includes a thin 'crown splash' around the perimeter of the impact, a deep cavity of air following the impactor, and a high, narrow jet of water that results from the collapse of the cavity. The new research, recently published in Physical Review Letters, demonstrates that airflow through the neck of the collapsing cavity reaches supersonic speeds despite low relative pressures between the air in the cavity and ambient pressure. Such an effect has no analogue in aerospace engineering or other sciences because of the highly dynamic nature of the collapsing nozzle structure." It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
You're right. That is funny!
The only way to appreciate the science of tossing stones into a lake is to be stoned yourself.
...that a story about tossing stones in a body of water would be picked up by an IT and technology news site.
Slashdot has officially jumped the shark with this splashing story. Really, who gives a toss?
It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
Funny or not, there are actually a few differences between the papers.
If you promise not to mess with the nature of my nozzle's highly dynamic collapsing nozzle-structure, I won't mess with yours - unless you want me to, of course, in which case I would expect to be able to count on reciprocity.
I think that's only fair, I mean, especially given that we just met and all. Let's just hope your nozzle hasn't been anywhere unseemly lately. I hate unseemly nozzles and I have no use for any with a rather static collapsing nozzle-structure, as I'm sure most people do. yuck....
Imagine what the U.S.'s technology leadership could've been like if we had put a President in the White House who truly understood this kind of cutting-edge science.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Neat! I want to see what that cone looks like as it develops, in super-slow motion.
Offtopic: I can't reply to the Racist Facial thread - all the Reply buttons are missing in both Camino and Firefox, and obviously I can post this thread. What gives?
Just some pieces of info for people who might not know:
Nowadays, all the major publishers dont have an issue if you post a prepring on arxiv, prl included.
If you want to get a preprint out, the procedure is as follows:
1) You put something on arxiv and submit it to PRL. /etc.
2) After a few weeks/months, you get your referee reports.
3) Then you revise it, and update your arxiv version.
4) Paper gets accepted. Paper is entering the editorial process, and you get proofs.
-> at this point, APS has contributed to the paper. The specific version proofed by PRL can no longer be uploaded to ARXIV
5) Final corrections, ready to print.
Nowadays, the proof and setting part is relatively minor. Most likely you will have written it in RevTex, and have PDF figures, so its an no issue.
But they still allow you to send them the text in word and the figures in phyical form (ink drawing, whatever), if you are really interested in it not getting published quickly.
So for most issues, a paper on Arxiv might be 99.9% identical to the final published paper, and only diiffer by the editorial issues. But you cannot know it. It might also represent a state from before the peer review.
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
After I RTFA I was all excited to see some cool video simulation or animations of this effect....
It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
If there's somebody stupid enough to pay for it, there's always somebody smart enough to charge for it.
Economic Darwinism hard at work, parting fools from their money since before 5,000 BC.
I work for the Department of Redundancy Department.
It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.
It's not that funny - the version subscribers can download from the APS has, amongst other things, a guarantee that it has had at least one cursory review. While it is true that the arxiv also filters out almost all spam and quite a few of the crackpot submissions, it is still chock-full of total bullshit. Say what you like about APS being the "accepts anyone" whore of the scientific community, the arxiv does not review submissions and probably never well.
Add to this the fact that the vast majority of people reading grabbing papers directly from the APS site will have either individual or institutional membership, thereby paying somewhere between $1 and $0.001 per paper, and you can hopefully see that the APS is not trying to rip people off or make everyone miserable. I imagine they're registered non-profit...
I'd love to see the testing process for this.
Tries 1 - 100
1. Plop ....
2. Plunk
3. Plunk
4. Bloop
5. Plunk
Give me a grant!
My younger brother discovered a key principle of the viscosity of fluids when he was 12 years old. He and his friend decided to drop a gigantic boulder down the center hole of an outhouse, they were standing over the "opening" to see the effect.
I imagine the sound was much "deeper" but their screams were really high.
It was a 2 mile walk to the nearest running water for them, our camping trips were never the same after that.
Tisha Hayes
I read the title as "The weird Science of Tossing Salad"
It's the quality that counts!
Cool technique. I wonder if they played "Smoke on the water" in the background ;P~~~
These posts express my own personal views, not those of my employer
If you can smell it, you are picking up some of its particles... but there have been studies with dyes that show during flushing, some water will hit the ceiling directly above the toilet.
How Profound:The high air speeds are shown to result from the "nozzle" being a liquid cavity shrinking rapidly in time.
Got Code?
While you were seriously offtopic, man has invented a solution for your ridiculous problem that only costs about 4 cents to produce, including manufacturing and shipping (at least in bulk).
Its called a toothbrush cover. Damn, how do scientist come up with these completely useless things designed to sucker money out of the kind of people who worry about spiders laying eggs in bananas, but only the top, so they cut the top off?
No wait, that's marketing.
For anyone who cares: Her name was: Amélie Poulain.
___ ;)
*Waiting for the about 3 french female geeks who get it*
Any sufficiently advanced intelligence is indistinguishable from stupidity.
What the fucking fuck
All I got was, "The Weird Science of Tossing" and thought you could get a grant for any kind of wankery these days.
Calling someone a "hater" only means you can not rationally rebut their argument.
Designed for mere mortals to read, should really have been included by the OP. http://physics.aps.org/viewpoint-for/10.1103/PhysRevLett.104.024501
1.) When the ball reaches the fluid it momentarily stops
2.) Just as the balls is completely below the fluid line it appears to stop again
3.) As the ball travels through the fluid, the INNER wall of separated fluid remains surprisingly straight for a surprisingly long period of time, yet the OUTER wall appears to be in constant motion
4.) Just before the ejected column of fluid collapses, a bright flash (a bubble perhaps) appears within the 'dome' of the ejection. This appears to change in intensity, becoming brightest just before the column collapses.
I'd like these particular events explained: e.g. The balls apparent momentary stop as it reaches the surface.
So, the big question is: when will the first computer game that features realistic water splashes be released?
I took this over the holiday break while bored:
http://links.cse.msu.edu:8000/members/matt_gerber/images/a/ac/Thumbtack.jpg
Lottery in June. Corn come soon....
Please do not read this sig. Thank you.
This explains the "Kerplunk" sound of a softball or slightly larger sized rock dropped into water. It's the initial splash "Ker" and the collapsing cone "Plunk".
-Eric