- Profile
Airborne Aerosol Transmission of COVID-19
Early in the COVID-19 pandemic health officials resisted the idea that the novel coronavirus was transmissible through tiny aerosol droplets rather than larger, non-buoyant droplets. One case that made headlines and helped shift opinion was that of an outbreak among patrons of a Guangzhou restaurant traced to a single, pre-symptomatic patient zero. The pattern of…
Reader Question: Kinetic Sand
An inquiring reader wants to know: How does kinetic sand work to make it flow like a liquid? Thanks! – 3 Year Olds Everywhere I confess I don’t have any firsthand experience with Kinetic Sand, but it certainly looks fun. It’s a colorful, moldable sand toy that holds together far better than your typical pile…
Wind Turbine Efficiency
Wind turbines face a paradoxical challenge: they must extract the wind’s kinetic energy while still allowing the air to pass. In this Minute Physics video, Henry gives a crash course on wind turbine efficiency, based on the restrictions of conservation of mass and conservation of energy. When the two are combined, they show that an…
Metallic Magma
Metallic paint flows like silver lava in this macro video from Chemical Bouillon. The paint has been mixed with an unknown fluid (my guess is alcohol) to produce the flows we see here. My suspicion is that we’re seeing solutal convection where variations in surface tension create convective flow within the liquid. What do you…
Oil-Coated Bubbles
Bubbles in industrial applications are often more complicated than a simple pocket of air surrounded by water. Here researchers investigate the formation of an air bubble coated in oil before it rises through water. The photo above shows a series of snapshots as the bubble forms. Initially, a droplet of oil sits pinned on the…
Meeting Without Mixing
When bodies of water meet, they don’t always mix right away. Here we see the confluence of the Back and Hayes Rivers in the Canadian Arctic. The Back River appears as a darker blue-green color compared to the light turquoise Hayes River. The different colors reflect the levels of algae and sediment carried in their…
How the Hummingbird Got Its Hum
Summer hikes in the Rocky Mountains are frequently pierced by a hum that can deepen to a bomber-like buzz as hummingbirds flit by. They’re so small and fast that they’re hard to see, but they’re never hard to hear. A new study pins down just where that telltale hum comes from. To determine the specific…
Underwater Explosions and Submarines
In the early days of submarines, it did not take physicists and engineers long to discover how destructive underwater explosions can be. In this Slow Mo Guys video, Gav gives us a glimpse of that destruction using a model submarine in a fish tank and several small explosives. You’ll have to be quick to notice…
“Columbia”
“Columbia” is a music video illustrated with fluid dynamics, chemistry, and biology by the Beauty of Science team. It’s got everything from precipitation to crystallization, from infrared imagery of wakes to timelapses of growing molds. How many phenomena can you identify? (Video and image credit: Beauty of Science)
Loopy Networks and Bird Lungs
When mammals breathe, air flows back and forth inside our lungs. But in birds that inhale and exhale get transformed into one-directional flow inside their lungs. To figure out how, researchers built loopy networks of pipes that turn oscillating flow into unidirectional flow. The simplest structure that does this is shown above. The main loop…