Watch a Former NASA Engineer Turn Sand Into Liquid—Then Take a Dip

iStock
iStock

NASA engineer-turned-YouTube host Mark Rober is known for regularly conducting zany science experiments in his own backyard and filming the results. More than a year after he went swimming in a sea of Orbeez, Rober's latest stunt features him taking a dip in a hot tub filled with liquid sand.

But wait: Wouldn't bathing in liquid sand be akin to taking a really grainy mud bath (albeit with great exfoliation potential)? Rober isn't technically wetting down the granular material, as he explains in the video below—he's making the sand sift, blow, and bubble using nothing but a nitrogen tank and some PVC pipe.

“If you take a tub of sand ... and then add air in just the right way, it basically becomes a liquefied soup,” Rober explains of the seemingly magical process. “In science this is known as a fluidized bed," or a bed of small, solid particles that are suspended and galvanized by an upward flow of gas.

The upwards-blowing air is equal to the downward force of gravity. This causes the sand to hover in equilibrium, and allows the grains to slide around like water. The top surface of the mix "is nearly frictionless," Rober says. "It's like an air hockey table. And then when you cut off the air, it freezes everything exactly where it's at," prompting the tub's ingredients to transform back into ordinary, heavy sand.

[h/t Twisted Sifter]

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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A Short, Sweet History of Candy Corn

Love it or hate it, candy corn is here to stay.
Love it or hate it, candy corn is here to stay.
Evan-Amos, Wikimedia Commons // Public Domain

Depending on which survey you happen to be looking at, candy corn is either the best or the worst Halloween candy ever created. If that proves anything, it’s that the tricolor treat is extremely polarizing. But whether you consider candy corn a confectionery abomination or the sweetest part of the spooky season, you can’t deny that it’s an integral part of the holiday—and it’s been around for nearly 150 years.

On this episode of Food History, Mental Floss’s Justin Dodd is tracing candy corn’s long, storied existence all the way back to the 1880s, when confectioner George Renninger started molding buttercream into different shapes—including corn kernels, which he tossed at actual chickens to see if it would fool them. His white-, orange-, and yellow-striped snack eventually caught the attention of Goelitz Confectionery Company (now Jelly Belly), which started mass-producing what was then sometimes called “chicken feed” rather than “candy corn.”

But what exactly is candy corn? Why do we associate it with Halloween? And will it ever disappear? Find answers to these questions and more in the video below.

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