Spin a hard boiled egg in a puddle of milk and you get a sprinkler. But how? The science starts at the surface. When the egg spins, the fluid touching its surface is dragged along due to friction, and, because of the fluid’s viscosity, other parts of the fluid will also be spun. Dynamics tells us that the velocity at the surface of the object varies with radius; the velocity at the bottom of a spinning sphere is much smaller than that at its equator because a particle at the equator traverses a larger distance in a single rotation. Likewise, the fluid touching the bottom of the egg is spun slower than the fluid just above it. Bernoulli’s principle tells us that, for an incompressible fluid, the pressure decreases as velocity increases, meaning that a favorable pressure gradient exists along the spinning convex surface. It is this pressure gradient that draws the fluid up the sides of the object. Near the equator, the pressure gradient is weakest and centrifugal force flings the the fluid outward. Surface tension, angular velocity, and viscosity all play a role in the jets and sheets created by the sprinklers. (Video credit: NPR Science Friday with Tadd Truscott et al)
Feynman on math vs. physics
Steve Cutts, what a genius.
University Stops Sales of Bottled Water
The Univ. of Vermont will become one of the first institutions nationwide to end the sale of bottled water on campus and mandate that one-third of drinks offered in vending machines be healthy options. The decision marks the advent of a long-awaited systematic sustainable beverage policy after years of lobbying by students and the greater campus community.
The announcement comes five months prior to the end of a ten-year contract with Coca-Cola of Northern New England that allowed the company to provide 100 percent of beverages in vending machines and 80 percent of bottled beverages served in retail, residential dining and catering, totaling more than 1.1 million bottles per year.
Read more: http://www.laboratoryequipment.com/news/2013/01/university-stops-sales-bottled-water
Happy Birthday Bill Nye!
Bill Nye (born November 27, 1955), scientist, engineer, comedian, author, and inventor, is a man with a mission: to help foster a scientifically literate society, to help people everywhere understand and appreciate the science that makes our world work. Making science entertaining and accessible is something Bill has been doing most of his life.
“My family is funny,” he says, “I mean funny in the sense that we make people laugh, not just funny looking.” Bill discovered that he had a talent for tutoring in high school, and while growing up in Washington, DC. He spent afternoons and summers de-mystifying math for his fellow students. When he wasn’t hitting the books, Bill was hitting the road on his bicycle. He spent hours taking it apart to “see how it worked.” Bill rode in the unusual Cannonball 300 a few times. It’s 300 miles in one day, from Seattle to Spokane, Washington. One year, he finished first unsupported. Now, he commutes by bike in the Los Angeles area. He’s down to just five bicycles.
Bill’s fascination with how things work led him to Cornell University and a degree in Mechanical Engineering. After graduation, he headed for Seattle and work as an engineer at Boeing. “There’s a hydraulic resonance suppressor “Quinke” tube on the 747 horizontal stabilizer drive system that I like to think of as my tube,” he says.
“I’ve always loved airplanes and flight. The space program was very important to me as a kid. I have a photo from the Apollo 11 mission with the caption, ‘Aldrin’s visor reflects Armstrong…’ Oh yeah, and they’re on the Moon!” exclaims Bill. Now, Bill and Buzz Aldrin are pretty well acquainted. “We see each other at space exploration events.”
It was in Seattle that Bill began to combine his love of science with his flair for comedy, when he won the Steve Martin look-alike contest and developed dual careers as an engineer by day and a stand-up comic by night. “I’ve never met Mr. Martin, but I’d love to. He created this tension during which the audience had to choose to laugh. So, the laughs were deep and real, like you had to be there- but you were,” says Bill. Eventually, Bill quit his day engineering day job and made the transition to a night job as a comedy writer and performer on Seattle’s home-grown ensemble comedy show “Almost Live.”
This is where “Bill Nye the Science Guy®” was born. The show appeared before Saturday Night Live and later on Comedy Central, originating at KING-TV, Seattle’s NBC affiliate. With fellow KING-TV alumni Jim McKenna and Erren Gottlieb, Bill made a number of award-winning shows, including the show he became so well known for, “Bill Nye the Science Guy.”
While working on the Science Guy show, Bill won seven national Emmy Awards for writing, performing, and producing. The show won 18 Emmys in five years. In between creating the shows, he wrote five kids’ books about science, including his latest title, “Bill Nye’s Great Big Book of Tiny Germs.”
Bill Nye is the host of three currently-running television series. “The 100 Greatest Discoveries” airs on the Science Channel. “The Eyes of Nye” airs on PBS stations across the country.
Bill’s latest project is hosting a show on Planet Green called “Stuff Happens.” It’s about environmentally responsible choices that consumers can make as they go about their day and their shopping. Also, you’ll see Bill in his good-natured rivalry with his neighbor Ed Begley. They compete to see who can save the most energy and produce the smallest carbon footprint. Bill has 4,000 watts of solar power and a solar-boosted hot water system. There’s also the low water use garden and underground watering system. It’s fun for him; he’s an engineer with an energy conservation hobby.
Bill’s next project is “Solving for X,” where he’ll show us how to do algebra along with the P, B, & J – the Passion, Beauty, and Joy – of math.
For the last few years, Bill has served as Vice President of The Planetary Society, the world’s largest space-interest group. He recently spoke on behalf of the Society at the International Astronautical Federation Congress in Glasgow, Scotland. He has also spoken in Hyderabad, India and Beijing, China. Unlike the days of the cold war, space Exploration has become an international undertaking.
One thing Bill is very proud of is the MarsDials, the two sundials on residing on Mars. These provide the only message to the future that’s been carried on spacecraft since the Voyager missions launched over 30 years ago.
It all started in 1998, when Bill was invited to a meeting at Cornell concerning the nascent missions to Mars. He took one look at the “photometric calibration targets,” and said, “Hey, we’ve got to make these into sundials!” Bill’s dad, Ned Nye, had been a prisoner of war and had lived without electricity for nearly four years. He became fascinated with sundials. When he got back to the US, he married his college sweetheart, Jacquie Jenkins. She had been recruited by the Navy to work on secret codes because she was good at math and science. Ned and Jacquie fostered Bill’s interest in science and Bill caught Ned’s love of gnomonics-sundials. Bill connected the Cornell scientists with Woody Sullivan, a University of Washington professor, astronomer and sundial expert. Now, we have the Spirit and Opportunity rovers on Mars both fitted with photometric calibration MarsDials. On their edges it describes the mission, and says, “To those who visit here, we wish a safe journey and the joy of discovery.” Bill says, “This is the essence of the scientific enterprise, the Joy of Discovery. That’s what the process of science is all about.”
Bill visits Cornell regularly as a Professor in his own right as part of the Frank H.T. Rhodes Visiting Professorship. In part as a tribute to his parents and their strong belief in the value of education, Bill has designed and funded a clock to be installed on Rhodes Hall at Cornell. It will be visible from a main thoroughfare, the stadium, and the baseball field.
Bill worked extensively to set up and promote the EarthDial Project, a set of sundials around the world visually reminiscent of the MarsDials and linked together on the World Wide Web. People everywhere can use the site and the process of building their own sundials to gain a deep understanding of geography, astronomy, and our society’s complex system of timekeeping.
Bill, the inventor, has two patents on educational products – a magnifier made of water and an abacus that does arithmetic like a computer. An occasional athlete, Bill has a patent pending on a device to help people learn to throw a baseball better. His next patent is an improved toe shoe for ballerinas.
America’s favorite stand-up scientist hasn’t changed much from that kid growing up in Washington, DC. He still rides his bike to work. He’ll pull out his Periodic Table of the Elements or his Map of Human Skin Tone from his wallet or show them to you on his phone display.
Bill Nye is a graduate of Cornell with a Bachelors of Science degree in Mechanical Engineering. He holds three Honorary Doctorate degrees from Rensselaer Polytechnic Institute, Goucher College, and Johns Hopkins. He has delivered commencement addresses at the University of California Santa Barbara, RPI, Goucher, Hopkins, Harvey Mudd College, and Caltech.
Bill is currently the Executive Director of The Planetary Society, the world’s large space interest organization.