Students Invent a Fire Extinguisher That Uses Sound

Scientists have used sound to do all kinds of amazing things, from levitation to brain surgery. Now, they've shown that sound can be used to put out fires.

Students Seth Robertson and Viet Tran from George Mason University have developed a way to harness sound and use it as a fire extinguisher. Low frequency sound waves—similar to the deep bass often found in hip-hop music—can apparently displace oxygen. If the oxygen is pushed away from the fuel, the fire will starve and go out.

The team started their endeavor after learning that sound had the ability to disrupt flames. They did not hear of any products on the market that worked, so they sought to make their own. Robertson and Tram originally experimented with high frequency sound between 20,000 and 30,000 hertz, but they found that 30 to 60 hertz was the ideal range. The students also learned to avoid music because the sounds were not consistent enough.

The resulting invention is a portable device that works similarly to a traditional extinguisher. A frequency generator was plugged into a power source and a cardboard tube then channeled the sound into a localized place. By pointing at the fire with the new invention, the flames dispersed, seemingly by magic.

This could do some serious good—not just on Earth, but also in outer space. "Fire is a huge issue in space," said Tran in a release. "In space, extinguisher contents spread all over. But you can direct sound waves without gravity," explained Robertson. The lack of foam is also perfect for outdoor settings or small rooms where the extra mess wouldn’t make sense.

The project has a lot of potential, but is not yet patented. “We still want to do a lot more testing," Tran said.

Kenneth E. Isman, a clinical professor at the University of Maryland, told the Washington Post that the invention still had some limitations. “One of the problems with sound waves is that they do not cool the fuel,” Isman said. “So even if you get the fire out, it will rekindle if you don’t either take away the fuel or cool it.”

Afternoon Map
The Most Searched Shows on Netflix in 2017, By State

Orange is the New Black is the new black, at least as far as Netflix viewers are concerned. The women-in-prison dramedy may have premiered in 2013, but it’s still got viewers hooked. Just as they did in 2017, took a deep dive into Netflix analytics using Google Trends to find out which shows people in each state were searching Netflix for throughout the year. While there was a little bit of crossover between 2016 and 2017, new series like American Vandal and Mindhunter gave viewers a host of new content. But that didn’t stop Orange is the New Black from dominating the map; it was the most searched show in 15 states.

Coming in at a faraway second place was American Vandal, a new true crime satire that captured the attention of five states (Illinois, Kansas, Massachusetts, Minnesota, and Wisconsin). Even more impressive is the fact that the series premiered in mid-September, meaning that it found a large and rabid audience in a very short amount of time.

Folks in Alaska, Colorado, and Oregon were all destined to be disappointed; Star Trek: Discovery was the most searched-for series in each of these states, but it’s not yet available on Netflix in America (you’ve got to get CBS All Access for that, folks). Fourteen states broke the mold a bit with shows that were unique to their state only; this included Big Mouth in Delaware, The Keepers in Maryland, The OA in Pennsylvania, GLOW in Rhode Island, and Black Mirror in Hawaii.

Check out the map above to see if your favorite Netflix binge-watch matches up with your neighbors'. For more detailed findings, visit

Afternoon Map
Monthly Internet Costs in Every Country

Thanks to the internet, people around the world can conduct global research, trade tips, and find faraway friends without ever leaving their couch. Not everyone pays the same price for these digital privileges, though, according to new data visualizations spotted by Thrillist.

To compare internet user prices in each country, cost information site created a series of maps. The data comes courtesy of English market research consultancy BDRC and, which teamed up to analyze 3351 broadband packages in 196 nations between August 18, 2017 and October 12, 2017.

In the U.S., for example, the average cost for internet service is $66 per month. That’s substantially more than what browsers pay in neighboring Mexico ($27) and Canada ($55). Still, we don’t have it bad compared to either Namibia or Burkina Faso, where users shell out a staggering $464 and $924, respectively, for monthly broadband access. In fact, internet in the U.S. is far cheaper than what residents in 113 countries pay, including those in Saudi Arabia ($84), Indonesia ($72), and Greenland ($84).

On average, internet costs in Asia and Russia tend to be among the lowest, while access is prohibitively expensive in sub-Saharan Africa and in certain parts of Oceania. As for the world’s cheapest internet, you’ll find it in Ukraine and Iran.

Check out the maps below for more broadband insights, or view’s full findings here.

Map of Internet costs in each country created by information site

Map of Internet costs in each country created by information site

Map of Internet costs in each country created by information site

Map of Internet costs in each country created by information site

Map of Internet costs in each country created by information site

[h/t Thrillist]


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