Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
How Hummingbirds Drink
Hummingbirds are incredible acrobatic fliers, capable of hovering for more than 30 seconds at a time, even in windy conditions. Their feeding habits are equally impressive. Many species of hummingbirds have a forked tongue, each half of which curls over like a partial straw. As the bird extends its tongue, its beak compresses the space…
Slipping Through a Soap Film
A droplet falling at high speed can pass through a soap film without breaking it. On impact, the drop stretches the soap film and ultimately only passes through by getting coated with a thin shell of soap film fluid. That liquid shell is separated from the original droplet by an extremely thin air layer. This…
Reader Question: Resonating Bottles
Reader shoebill-san asks: why does it make that weird sound when i blow over a bottle? i did a science experiment in college where we looked at the resonance in a beaker at different water levels, is it like that? related? Blowing across the top of a bottle creates what’s called Helmholtz resonance, where air…
Cycling Skinsuits and Vortex Generators
It didn’t take long for an aerodynamic controversy to crop up in this year’s Tour de France. At the 14km individual time trial, riders from Team Sky wore custom Castelli skinsuits with integrated dot-like patterns on their upper arms (shown above). By the next day, a sports scientist with a competing team cried foul play,…
When Walls Chirp
If you’ve ever clapped near a wall with a corrugated surface, you may have noticed some strange echoes. Surfaces like these can cause a chirping sound to observers. The reason, as Nick Moore explains in the video above, is that the original sound reflects off the corrugations at different times and travels back to the…
“Fractal”
Timelapses are a wonderful way to capture the power and majesty of storms like the supercell thunderstorms featured in Chad Cowan’s “Fractal”. The video contains snapshots from six years’ worth of storms over the US’s Great Plains. The highlights include some spectacular mammatus clouds (0:30) and excellent billowing cloud formation (1:27) with turbulence every bit…
Schooling in Soap Films
In sports, flocks of birds, and schools of fish, we’re accustomed to thinking that the followers get an aerodynamic or hydrodynamic advantage over the leaders, but this may not always be the case. Here are two flags placed one after another in a soap film flowing from top to bottom. The flags are passive, meaning…
How Cycling Position Affects Aerodynamics
New FYFD video! How much does a rider’s position on the bike affect the drag they experience? To find out I teamed up with folks from the University of Colorado at Boulder and at SimScale to explore this topic using high-speed video, flow visualization, and computational fluid dynamics. Check out the full video below, and…
Watching Radiation
We’re used to radiation being invisible. With a Geiger counter, it gets turned into audible clicks. What you see above, though, is radiation’s effects made visible in a cloud chamber. In the center hangs a chunk of radioactive uranium, spitting out alpha and beta particles. The chamber also has a reservoir of alcohol and a…
Glacial Remains
The high walls of this alpine canyon were cut by flowing glacial ice. This type of amphitheater-shaped valley is known as a cirque. The photo shows one of the Chicago Lakes on Mount Evans in the Colorado Rockies. The glacier that once sat here carved the steep walls you see in the background but also hollowed out…