Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Wrinkles on Collapsing Bubbles
As a bubble sitting on a pool collapses, wrinkles form around its edges. Visually, the result is quite similar to the wrinkles one gets on an elastic sheet. Unlike the solid sheet, though, the bubble’s film varies in thickness; we know this because of the fringes shown in the enlarged inset of the poster. Researchers…
Whiskey Webs
Unlike scotch whisky, when American bourbon whiskeys are diluted, they form unique web-like evaporation patterns. These differences arise in part from the way the liquors are aged: scotch is aged in re-used barrels, whereas bourbons require aging in a new, charred American white oak barrel*. During aging, the whiskey picks up water-insoluble chemicals from the…
Albedo Effect
Temperature isn’t the only factor that determines how ice will melt. In this photo, a dark oak leaf absorbed more solar radiation than the reflective ice around it, causing the ice beneath it to melt. Scientifically, this effect is described by albedo; darker, more absorptive surfaces like the leaf have a lower albedo, whereas light,…
Visualizing Radiation
Radiation is invisible, but it’s not too difficult to build an apparatus that lets you see it. This video shows the ghostly aftermath of passing radiation in a cloud chamber, one of the first set-ups used to study radiation. The chamber contains a radioactive source and chilled isopropyl alcohol. The alcohol forms a supersaturated vapor…
Insect-Inspired Flight
Insects are incredibly agile and resilient fliers, capable of colliding and recovering without damage. Engineers are only beginning to capture these characteristics in their robots. Here, engineers use a soft actuator — a rubber cylinder coated in carbon nanotubes — to drive their robot’s flight. When voltage is applied across the carbon nanotubes, the rubber…
Fluid Chains
In this video, Steve Mould tackles a question many of us have likely wondered: just why does falling water make this chain-like shape? When pouring from a slit-like orifice, water jets take on this undulating pattern. While I have no issue with Steve’s explanation of surface tension oscillations driving the shape, I’ll quibble a little…
Meltwater Tracking Via Seal
Monitoring meltwater from Antarctic glaciers is critical for understanding our changing climate, but such remote and inaccessible regions are tough to collect data in. So researchers are turning to local workers to help them gather data. By collecting and analyzing data from seal tags, researchers have mapped new seasonal variations in meltwater flows around Pine…
Superior Mirage
This photograph of a ship seemingly floating far above the water is not some Photoshop fakery; it’s physics creating the illusion. It’s an example of what’s known as a superior mirage — superior because the mirage appears above the object’s actual location, unlike the mirages you see above the road on a hot day. In…
“Dancing With Danger”
Filmmaker Chris Bryan captures surfer Kipp Caddy as he rides an enormous wave in “Dancing With Danger.” Nothing quite captures the majesty of these powerful flows like high-speed videography. Enjoy the break, the spray, and those awesome rib vortices. (Image and video credit: C. Bryan)
Jumping Frost
Liquid water is easily electrically charged, due to its polar nature. That’s why rubbing a comb is enough to deflect a stream of water. Ice is harder to charge, but it can happen, especially when there are temperature gradients across the ice. That’s the key behind this study of jumping frost. When ice crystals grow…