Of all the things in the physical world we think we know a lot about, water is definitely among them. Nonetheless, by precisely shaking a shallow container of water, researchers have now observed two new types of waves that have never been observed before in water--and one that has never been observed in any other media either.
To conjure the waves, the researchers used what is known as a Hele-Shaw cell mounted on a small shake table. A Hele-Shaw cells is a container consisting of two parallel transparent plates separated by a small gap, much like an ant farm (see images above and .gifs below). In this case, the gap between them was 1.5 millimeters, or less than 6 hundredths of an inch.
As they ratcheted up the oscillation amplitude of the shaker, a high-speed camera recorded the surface deformation of the water inside the Hele-Shaw, revealing two new kinds of strange waves (both known as Faraday waves). One has an even symmetry, the other an asymmetric appearance, with a larger upper half and a smaller lower half.
All that might sound pretty pedestrian, but these properties could have implications for a range of other mechanisms in other fields like chemistry, biology, and optics. And then there's sea waves, about which we still have much to learn. These new wave architectures may not look like much, but they inform our knowledge about large amplitude waves and their formation in the ocean. That's a good thing to know about, as large-amplitude waves also go by the names "rogue waves" and "tsunamis" in certain contexts.
With such a small gap, is it possible these waves are created in part by the capillary action of the water on the plates?
-IMP ;) :)
the first wave looks similar to when a drop of water is dropped into water and the water absorbes the impact and then reverberates on itself.
@extremechiton, I thought the same thing.. it looks like nothing more than a cross section of what water does when something is dropped into it.
@IMP.. the second one looks like it is very much a product of waveform that is compromised by the plates themselves..
And since the gif's only show part of the whole waveform played over and over, it's a bit deceiving.
Playing Devil's Advocate since 1978
"The only constant in the universe is change"
-Heraclitus of Ephesus 535 BC - 475 BC
to IMP, thats exactly what i was thinking when i first saw that a Hele-Shaw cell was being used for this research.
Rougue ocean waves comes to mind when i see this... once unbelievable, now very much so!
In whose world does 1.5 mm = 6/100 of an inch? What a basic mistake for a science site?!?
Sorry for my ignorance, but i got it wrong-DOH-it is correct.
I was reading The Genius of China which occupied all of Needham's life, and on page 42 under Engineering is a picture of a standing wave created in a specially cast bronze bowl from the 5th century. Water is now in the science eye as AGN produce water. I suspect that water will be 'discovered' to be a fundamental component of matter formation at the center of our galaxy and others.