Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Wind Turbine Physics
Over the years, wind turbines have gotten tall with long, thin blades. This MinutePhysics video delves into the reasons for those changes. They’re all aimed at generating more wind power and doing so with greater efficiency. I’ll add one caveat to the video, though, because you may wonder how modern wind turbines can be fast…
The Sounds of Leidenfrost Stars
On a hot surface, droplets can float on a layer of their own vapor and vibrate in star-like shapes. These so-called Leidenfrost stars also make noise, with distinct beats that match the oscillations of the vapor layer beneath them. Researchers found that the frequency of the sound shifts with droplet size, increasing as the drop…
Blue Jets
Blue jets are a mysterious form of lightning that shoots upward from intense thunderstorms. The image above comes from one of the first color videos of blue jets, taken by an astronaut aboard the International Space Station. Scientist think blue jets form during an electric breakdown between the positively-charged upper region of a cloud and…
“Liquid Skies”
“Liquid Skies” by Roman De Giuli is full of colorful but nebulous fluid imagery. The visuals consist of liquids like paint, ink, and alcohol filmed in macro atop paper. You can catch a behind-the-scenes glimpse of De Giuli at work here. (Image and video credit: R. De Giuli)
Acidic Sea Spray
As waves crash and break, they generate a spray of droplets — known as aerosols — that make their way into the atmosphere. Researchers investigated the chemistry of these aerosol droplets by generating spray in a wave tank filled with ocean water. They found that aerosol droplets are far more acidic than the ocean they…
Spiderwebs and Stratocumulus Clouds
Stratocumulus clouds cover about 20% of Earth’s surface at any given time, and they form distinctive patterns of lumpy cells separated by thin slits. Because of their interconnectedness, researchers nicknamed these narrow regions spiderwebs. New simulations show that evaporative cooling along the cloud tops drives the formation of these spiderwebs (Image 2). Without it (Image…
The Unsinkable Pygmy Gecko
The Brazilian pygmy gecko is a tiny inhabitant of the Amazon rainforest, growing to no longer than 24 mm. But these tiny lizards have some incredible superpowers when it comes to surviving the rainforest’s deluges. The gecko’s surface is superhydrophobic — water repellent — thanks to millions of tiny hairs that create air pockets between…
The Fluidity of Worm Blobs
The aquatic blackworm forms blobs composed of thousands of individual worms for protection against evaporation, light, and heat. The worms braid themselves together (Image 1). Once a blob forms, it is extremely viscoelastic, displaying properties both solid and fluid in nature (Image 2). The worm blobs act like a collective; they bunch up to prevent…
“Flux Capacitor”
Sandro Bocci’s short film “Flux Capacitor” explores the geometry and dynamics of soap films. When you dip wire models into soapy solution, the films that cling to the model can form complicated shapes as surface tension works to minimize the overall surface area. Bocci’s macro photography highlights the intense flows going on in the narrow…
Gathering Droplets
In deserts around the world, plants have adapted to collect as much moisture as they can. Geometry aids them in this endeavor because droplets on the tip of a cone will move toward its thicker base. The motion takes place due to a imbalance in surface tension forces on either end of the droplet. As…