If you stand on a bridge and watch the current flow past pylons below, you’ll see disturbances marking the wakes. Dragging a rod – or an oar – at a high Keep reading
Tag: cavity
Reducing the Force of Water Entry
As anyone who’s jumped off the high board can tell you, hitting the water involves a lot of force. That’s because any solid object entering the water has to accelerate Keep reading
Oil-on-Water Impact
Although many people have studied droplet impacts over the years, there’s been remarkably little work done with oil-on-water impacts. One of the things that makes this situation different is that the oil Keep reading
Reader Question: Inside a Vortex
Reader embersofkymillo asks: Hey FYFD, could you do some analysis/explanations behind the physics of this vortex stuff? I love when you do spots on Slow Mo Guys vids and figured Keep reading
Water Impacts
In the clean and simplified world of the laboratory, a droplet’s impact on water is symmetric. From a central point of impact, it sends out a ring of ripples, or Keep reading
Entrained
When an object hits water whether it draws air in with it depends on its shape, impact speed, and surface characteristics. In this experiment, though, there’s a bit of a Keep reading
Using Paper to Avoid Splashback
Daily life and countless pool parties have taught us all that objects falling into water create a splash. Sometimes that splash is undesirable, and while there are many ways to Keep reading
Sandy Splashes
Sand and other granular materials can be strikingly fluid-like. Here the impact of a solid sphere on sand generates a splash remarkably similar to what’s seen with water. When the Keep reading
Galapagos Week: Diving Birds
One of my favorite things to do while we were sailing along the Galapagos was watching the blue-footed boobies hunt. Like the gannets shown above, boobies are plunge divers. They Keep reading
Squishy Impacts
How spheres impact water has been studied for more than a century. The typical impact for a rigid sphere creates a cavity like the one on the upper left – Keep reading