A Leidenfrost droplet impregnated with hydrophilic beads hovers on a thin film of its own vapor. The Leidenfrost effect occurs when a liquid touches a solid surface much, much hotter than its boiling point. Instead of boiling entirely away, part of the liquid vaporizes and the remaining liquid survives for extended periods while the vapor layer insulates it from the hot surface. Hydrophilic beads inserted into Leidenfrost water droplets initially sink and are completely enveloped by the liquid. But, as the drop evaporates, the beads self-organize, forming a monolayer that coats the surface of the drop. The outer surface of the beads drys out, trapping the beads and causing the evaporation rate to slow because less liquid is exposed. (Photo credit: L. Maquet et al.; research paper - pdf)
Hank shares the week in science news, including the top 10 new species discovered in 2014, and the start of construction of the first fusion reactor. It’s gonna be big!
Complete Top 10: http://www.esf.edu/Top10/
The Search for Antimatter
If you don’t have any idea what antimatter is, you don’t have to feel bad - the brightest minds in the world have only recently begun to understand what it is and how it works. Hank gives us the run down on what we know about antimatter, and what we’re still trying to figure out.
Is There Gravity in Space?
In a word, “yes” - space is packed with gravity. Hank explains how Isaac Newton described how gravity works, and why even though it seems that things are floating in space, they’re still effected by gravity. Every object in the universe is constantly attracting every other object in the universe.
Richard Feynman, The Great Explainer
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Aside from being a great scientist and teacher, Richard Feynman was a kooky and curious guy who played the bongos, painted, and did math in strip clubs. Hank shares his Feynman love fest with us in this episode of SciShow: Great Minds.
Fun With Potatoes & Physics! A SciShow Experiment
Hank uses a favorite subject of the YouTube community - the potato gun - to teach us about the principles of pneumatics, which use the potential energy of compressed gas to do work in lots of useful machines every day.
SciShow: Dark Matter
Physicists estimate that dark matter accounts for about twenty three percent of the known universe - the only problem is that no one really knows what it is…
3 Physics Experiments that Changed the World
Physics investigates why the universe behaves the way that it does, and today, Hank tells us about the three physics experiments that he thinks were the most awesome at helping us understand how the universe works.
Explaining Colour Charge
It’s particle physics time! In the Standard Model, quarks are the the building blocks of hadrons (i.e. protons and neutrons), which in turn are the building blocks of the atom. There are two types of hadrons: baryons, made up of three quarks, and mesons, made up of one quark and one antiquark. Protons are baryons, and so they’re made up of two up quarks and one down quark—and at first glance, this appears to violate the Pauli Exclusion Principle, which states that no two identical objects can occupy the same place. So, how can two up quarks be bound together in the same proton? It’s proposed that aside from properties like mass and spin, quarks have another more unique property: the colour charge, which binds them together. There are six manifestations, described as red, green, blue, antired, antigreen, and antiblue, but colour charge actually has nothing to do with visible colours—it’s just a convenient label, because it can be related to the three primary colours. The property allows quarks to obey the Exclusion Principle, as a hadron can contain three different ‘colour’ quarks, and a meson can contain a quark and anti quark of the corresponding colour and anticolour. The colour charge does more than that, though: it’s a description of how a quark responds to the strong nuclear force. In the Standard Model, four fundamental forces hold elementary particles together—strong force, weak force, electromagnetic force, and gravity—and since quarks interact via the strong force, colour charge is basically what holds quarks together—and by extension, what holds together all matter.
Let’s ask ourselves…what exactly is going on here? I mean, I know, it’s a movie, it’s animated, it’s for kids, and SpongeBob lives in a pineapple and wears pants and has bonfires underwater but really, let’s just look at this.
What’s in those bags? What are the bags in? Why would bags of water float in water? How on Earth does that make visual sense to anyone ever in the history of the world! The bags aren’t even taking their natural shape!
THIS IS A DISASTER OF TERRIBLE PHYSICS!