Watch Richard Feynman Explain Fire

United States Army // Public Domain
United States Army // Public Domain

Physicist Richard Feynman was a master explainer. His physics lectures are a model of clarity. His specialty is explaining one concept in the context of another concept the listener already understands.

In the video below, Feynman tackles the seemingly simple question: What is fire? This is a hard question for many of us to answer without referencing fire itself. Fire is burning. Fire is what happens when you light a match. Fire is a reaction. But aside from our existing knowledge of its effects (like flame), what is it and how does it happen? What else is fire like that we understand already?

In 1983, Feynman answered this question (among others) for the BBC on its Fun to Imagine series. He starts like so:

The atoms like each other to different degrees. Oxygen, for instance in the air, would like to be next to carbon, and if they're getting near each other, they snap together. If they're not too close though, they repel and they go apart, so they don't know that they could snap together.

It's just as if you have a ball that was [rolling and] trying to climb a hill and there was a hole it could go into. Like a volcano hole, a deep one. It's rolling along, and it doesn't go down in the deep [volcano] hole, because it starts to climb the hill and it rolls away again. But if you make it go fast enough, it'll fall into the hole.

So if you set something like wood in oxygen...there's carbon in the wood from a tree. And the oxygen comes and hits the carbon, but not hard enough. It just goes away again. The air is always [moving but] nothing's happening. If you can get it fast enough, by heating it up somehow...a few of [the atoms] come past, a few of them go over the top, so to speak.

So there you have it. If you understand what a volcano looks like and how a ball rolls under normal earth gravity, you have the start of this mental image for how fire works. Feynman's explanation manages to convey chemical behaviors in terms humans intuitively understand—the way a ball rolls—because that's the world we live in. Watch this for a delightful explanation:

The BBC has more clips (in better quality) at this slightly vintage website. You can also download the entire hour-long lecture from the Internet Archive.

[h/t: Kottke.org.]

Watch Kit Harington Gag After Having to Kiss Emilia Clarke on Game of Thrones

HBO
HBO

The romance between Jon Snow and Daenerys Targaryen might be heating up on Game of Thrones (though that could change once Jon shares the truth about his parentage), but offscreen, Kit Harington and Emilia Clarke's relationship is decidedly platonic. The two actors have gotten to be close friends over the past near-10 years of working together, which makes their love scenes rather awkward, according to Harington.

A new video from HBO offers a behind-the-scene peek at "Winterfell," the first episode of Game of Thrones's final season. Starting at about the 12:20 mark, there's a segment on Jon and Dany's date with the dragons and what it took to create that scene. Included within that is footage of the two actors kissing against a green screen background (about 13:50), which would later be turned into a stunning waterfall. But when the scene cuts, Harington can be seen faking a gag at having to kiss the Mother of Dragons.

“Emilia and I had been best friends over a seven-year period and by the time we had to kiss it seemed really odd,” Harington told The Mirror, then went on to explain that Clarke's close relationship with Harington's wife, Rose Leslie, makes the intimate scenes even more bizarre. "Emilia, Rose, and I are good friends, so even though you’re actors and it’s your job, there’s an element of weirdness when the three of us are having dinner and we had a kissing scene that day."

As strange as it may be, Harington finally came around and admitted that, "I love Emilia and I’ve loved working with her. And it’s not hard to kiss her, is it?"

[h/t Wiki of Thrones]

From Cocaine to Chloroform: 28 Old-Timey Medical Cures

YouTube
YouTube

Is your asthma acting up? Try eating only boiled carrots for a fortnight. Or smoke a cigarette. Have you got a toothache? Electrotherapy might help (and could also take care of that pesky impotence problem). When it comes to our understanding of medicine and illnesses, we’ve come a long way in the past few centuries. Still, it’s always fascinating to take a look back into the past and remember a time when cocaine was a common way to treat everything from hay fever to hemorrhoids.

In this week's all-new edition of The List Show, Mental Floss editor-in-chief Erin McCarthy is highlighting all sorts of bizarre, old-timey medical cures. You can watch the full episode below.

For more episodes like this one, be sure to subscribe here.

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