Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
“Discovery”
Colors stream and mix in Rus Khasanov’s short film “Discovery.” Droplet-like liquid lenses float in the mixture until ethanol or other ingredients cause them to spontaneously rupture, sending their interior flowing outward until the lens reaches a new equilibrium. Gradients in surface tension guide Marangoni flows across the screen. There’s never-ending beauty in the world…
Bubble Growth, Inspired By Art
Eighteenth- and nineteenth-century French painters like Chardin and Manet had a certain fascination with bubble-blowing physics. Both left behind artwork depicting children blowing soap bubbles through straws. Now researchers are exploring this bubble-making method in a recent study. To blow a bubble from a straw or other narrow constriction, there are three basic stages. In…
The Physics of Vowels
Blow across the top of a glass bottle, and you’ll get a whistle-like sound. Put some liquid in there and the pitch of the sound changes. Our vocal tracts are basically the same thing: a tube with a hole at the end. But as Joe Hanson shows in this Be Smart video, our ability to…
Puddle Depth Matters for Stalagmites
In a cave, mineral-rich water drips from the ceiling, spreading ions used to build stalagmites. A recent study considers how the depth of a pool affects the droplet’s splash and how material from the droplet spreads. The authors found several scenarios that vary widely depending on pool depth. A drop falling into a shallow pool…
Tongan Eruption
In January 2022, the Hunga Tonga-Hunga Ha’apai volcano erupted spectacularly, sending waves around the world through the air, water, and ground. In many ways, it was unlike any eruption scientists have observed, though they think it bears similarities to the 1883 eruption at Krakatoa. This video summarizes some of the research to come out of…
Icelandic Glacial Caves
Expedition guide and photographer Ryan Newburn captures the ephemeral beauty of the glacial caves he explores in Iceland. These caves are in constant flux, thanks to the run and melt of water. The scalloped walls are a sign of this process of melting and dissolution. The icicles, too, hint at ongoing melting and refreezing. Caves…
Studying Earth’s Interior
The Earth’s interior is almost entirely inaccessible to humanity, so how do we know what it consists of? As explained in this video, our knowledge of the planet’s interior is based on measuring waves sent out by earthquakes and nuclear blasts. Both produce two kinds of waves — pressure waves (P-waves) and shear waves (S-waves)…
Anabranching Riverways
The Diamantina River in Australia is dry for much of the year. But seasonal rains flood its riverbeds and provoke a bloom of vegetation along its banks. This false-color satellite image shows the river in April 2023; land appears pale and reddish, the river and its sediment blue, and vegetation a bright green. The Diamantina…
Colorful Drainage
Bright colors mark this slowly draining soap film. The film sits slightly off-horizontal, so flow shifts over time from the top of the frame to the bottom. The fluid is also evaporating. All the faster shifts are caused by ambient air currents from the room. The colors of the film are directly related to the…
Sniffing in Stereo
Snakes’ forked tongues have long inspired fear, but, in reality, they are part of a highly-effective sensory system. When snakes flick out their tongues, they waggle them up and down about 15 times a second. That motion draws air inward toward the tongue (Image 2), allowing scent molecules to stick to the saliva on either…