Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
How Water Droplets Charge Up
Rubbing a balloon on your hair can build a significant electrical charge. Water droplets have the same issue when they slide across a hydrophobic, electrically-insulated surface. A new study models why these charges build up and tests the model both experimentally and through simulation. They focused their theory on three effects that determine how much…
Mardi Gras Pass
The mighty Mississippi River has long been bound by humanity’s efforts. To keep the river in place and control its flooding, engineers have built levees, canals, and other structures. But those efforts have come with costs. Where the wild Mississippi used to deposit sediment and build new land, the bound river sends its sediment out…
How to Run on Water
Ahead of the Olympics, I’ve written a feature article for Physics World that explores how basilisk lizards and grebes run on water and what it would take for a human runner to do the same. Check it out! (Image credit: B. Mate; see Physics World)
A Shallow Origin for the Sun’s Magnetic Field
The Sun‘s complex magnetic field drives its 11-year solar activity cycle in ways we have yet to understand. During active periods, more sunspots appear, along with roiling flows within the Sun that scientists track through helioseismology. Longstanding theories posit that the Sun’s magnetic field has a deep origin, about 210,000 kilometers below the surface. But…
Wasps in Flight
Personally, I’ve had some bad encounters with wasps, but Dr. Adrian Smith of Ant Lab feels the insects receive short shrift. In this video, he shows many species in the order — most of which are venomless and stingless. In high-speed video, their flight is mesmerizing. Wasps have separate fore- and hindwings, but during flight,…
“Emitter”
For this latest experimental film, artist Roman De Giuli provides a glimpse of the unique fluid art machine he’s built over the last 3.5 years. With 10 channels driven by peristasltic tube pumps and stepper motors, his “printer” drips up to 10 colors on a paint-covered, tilted canvas to create these beautiful images. As he…
Viscous Fireworks
Inject a less viscous fluid into a gap filled with a more viscous fluid, and you’ll get finger-like patterns spreading radially. Here, researchers put a twist on this viscous fingering by taking turns injecting different liquids. Each injection cycle disrupts what came before, layering fingering patterns on fingering patterns. The results resemble fireworks. Happy 4th…
Fish Ladders Keep Species Swimming
Dams often use fish ladders to help migratory species make their way upstream without interruption. In this video, Grady from Practical Engineering discusses some of the considerations that go into this special infrastructure and what kinds of designs work for different species. The first challenge for any dam is attracting fish to the ladder, which…
Sensing Sound Like Spiderwebs
Most microphones — like our ears — work by sensing the tiny pressure changes caused by a sound wave‘s passing. But for microphones built this way, the smaller they get, the more sensitive they are to thermal noise. That’s one reason that the tiny microphones in a laptop or webcam just don’t sound as good…
Ancient River Branch Discovered Near Giza Pyramids
Today the pyramid complex at Giza sits kilometers from the Nile River, raising longstanding questions about how ancient builders moved the enormous stones that make up each structure. A new study using radar satellite imagery, geophysical data, and deep soil coring identified a previously unknown ancient branch of the Nile that ran alongside the Giza…