The Leidenfrost Effect is a lovely sounding name for some very strange and nifty physics.
When you heat up a liquid, it will, eventually, boil away into a gas. Different liquids have different boiling points. But here's the weird catch: When you suddenly put a liquid in contact with something much, much hotter than its boiling point, the liquid doesn't instantly evaporate. Instead, it forms a little cushion of vapor between itself and the heat source. You can imagine it like a hovercraft moving over the surface of a lake. The cushion doesn't prevent evaporation—and it doesn't last long—but it does slow down evaporation enough that you can see the liquid moving around on the hot surface for little bit like everything is just fine and dandy.
This video was made as a promotional piece for Modernist Cuisine. The Leidenfrost Effect matters for cooking because it allows you to tell when you have successfully heated up a pan. If the temperature of the pan is above the Leidenfrost point, then you can sprinkle it with water and watch the droplets bandy about on the hot metal. In this case, though, they used liquid nitrogen.
Olivia P. Judson’s paper in Nature, The energy expansions of evolution, presents a novel, beautifully written and presented frame for looking at the history of life on Earth: as a series of five epochs in which energy became more abundant and available to lifeforms, allowing them to scale up in complexity and fecundity: geochemical energy, […]
Beatboxer Tom Thum had ENT doctor and laryngeal surgeon Dr Matthew Broadhurst shine an endoscopic camera down his throat while beatboxing: “I wanted to find out how my larynx functioned when beatboxing compared to how it functions normally with speech, and whether or not there were any abnormalities in my laryngeal anatomy. I also had […]
Gastric bypass surgery is remarkably effective at promoting weight-loss (it cuts the long-term risk of early death from morbid obesity by 40%), and it’s long been presumed that the major action by which it worked was that, by bypassing the parts of the gut where most food absorbtion takes place, it limited the calories that […]
If you are camping during rainy season, or just want a TSA-approved lighter, these plasma torches make perfect travel companions. These gas-free lighters create a small plasma beam that’s safer than butane to use and more environmentally friendly. It creates a super-hot, splashproof flame so you can get a campfire going, or have a smoke […]
If you don’t want to get stuck footing the bill for a hit and run, this dashboard-mounted camera offers up to 2K resolution to make sure you always have a reliable witness, and it’s available in the Boing Boing Store for 30% off it’s usual price.The PapaGo mounts unobtrusively to your windshield to see everything […]
While some people still maintain that everything in Apple’s walled garden “just works” and is immune to the rampant malware of the Windows world, the reality is different. The Mac’s growing market share has made it a much more viable target for malicious actors, and its built-in tools aren’t always enough to fix things. Drive […]