leon foucault born september 18 1819
Leon Foucault pendulum google doodle
leon foucault 194 on september 18. discovered earth rotates with pendulum. celebrated with google doodle.
How Léon Foucault taught us to watch the world spin
Léon Foucault and his pendulum demonstrated the turning of the Earth. Google honored the French physicist with an interactive doodle.
It’s easy to forget that while you read this article, you and your computer screen are racing through space at a nearly unimaginable speed. The earth constantly rotates on its axis at 1,037 miles per hour, orbiting the sun at 67,000 m.p.h. And the solar system whips around the galaxy at more than 420,000 m.p.h.
Two centuries ago, it was difficult for scientists to model intricate planetary orbits. Léon Foucault helped devise a method to make celestial orbits a bit easier to understand.
Wednesday marks the 194th anniversary of the French physicist’s birth. To celebrate Mr. Foucault and his breakthrough pendulum, let’s take a look at how he was able to model Earth’s rotation.
Jean Bernard Léon Foucault was born in Paris in 1819. While Foucault received a medical education, the profession did not quite suit him. The young doctor is said to have a distaste for bloody medical dissections. But Foucault was brilliant when it came to making models, tools, and devices.
And Foucault’s craftsmanship came in handy.
Foucault and a series of teachers, bosses, and partners tackled many scientific questions by building contraptions that could make hard-to-grasp phenomenas more tangible. Foucault was able to measure the speed of light. He improved the daguerreotype, an early form of photography. He found a way to prove that light is a wave, not a beam of particles. He named the gyroscope, a stabilizing tool found in everything from toys to the International Space Station.
In 1851, Foucault made one of his best-remembered experiments: the scientist devised the first model to demonstrate the rotation of the earth on its axis.
People had tried many different ways to explain Earth’s rotation before Foucault. One group had even launched cannon balls up into the air with the hopes that the world would spin enough that they could measure the deviation once the ball plummeted back to earth. Compared to that loud, inaccurate (and dangerous) plan, Foucault’s solution was remarkably elegant. He strung up a brass weight at the end of six-foot wire. The metal ball hung over a pile of damp sand, just close enough that the brass brushed against the sand as it swung slowly back and forth. At first, the pendulum simply carved a straight line in the sand. But over the course of several hours, the line turned into a bow-tie shape.
Newton’s laws of motion state that an object will not change direction unless another force hits it. This means that while Foucault’s pendulum kept swinging in the same direction, the earth (and the sand on the ground) turned underneath it. It’s as if you drew a line back and forth repeatedly on a piece of paper, but then slowly rotated the sheet as you kept drawing – eventually the lines would form a circle.
Foucault’s experiment became a sensation. The French government even ordered a large-scale version that would hang inside the Pantheon in Paris, with a 219-foot, 61-pound pendulum suspended from the building’s dome. Modern-day pendulums hang in the United Nations headquarters in New York, the California Academy of Sciences in San Francisco, the Boston Museum of Science, and many other locations.
Since Earth spins on an axis, each of these “Foucault pendulums” turns at a slightly different rate, demonstrating that different parts of the globe rotate at different speeds. At the North Pole, a Foucault pendulum would turn 15 degree per hour, making a full 360-degree circle each day, while in Paris, the pendulum would only turn about 11 degrees an hour, requiring 32.7 hours to make a complete round. On the equator, the pendulum would not appear to spin at all.
In recognition of his many achievements, Foucault is among the 72 French engineers, scientists, and mathematicians whose names are engraved on the Eiffel Tower.
via and for more see http://www.csmonitor.com/Innovation/Tech-Culture/2013/0918/How-Leon-Foucault-taught-us-to-watch-the-world-spin and http://www.youtube.com/watch?v=O3wJsbvPSBk
minerva to start as tuition free and be like Harvard
Entrepreneur starts his version of Harvard, tuition-free
The San Francisco-based Minerva Project is undertaking an ambitious effort to remake the higher education model and attract the world’s top students.
SAN FRANCISCO — Minerva Schools of KGI doesn’t yet have accreditation, a campus or even a full faculty roster, but it is offering something even Harvard can’t — four years of free tuition for its first matriculating class.
The San Francisco-based Minerva Project, an ambitious effort to remake the higher education model, announced its tuition plan on Tuesday in hopes of attracting some of the world’s most talented and academically competitive students for the class that will enroll in the fall of 2014.
Although many details of the new school are still to be ironed out, students in subsequent years will pay tuition of $10,000 a year along with about $19,000 annually for room and board — still well below the cost of many other top U.S. universities that can run upward of $50,000 and $60,000 a year.
“Not only are we looking at students who are intellectually brilliant, we are looking for students who have a deep intellectual thought, deep integrative thought, worldliness, excitement about seeing the world, and maturity,” said Minerva founder Ben Nelson, who ran photo service Snapfish until he sold it to Hewlett Packard in 2005.
“We’re asking a lot of them,” he said about the first class of students. “We’re asking them not only to be the first students at Minerva, but to help us shape it.”
That will include providing constant feedback, he said in an interview, adding the first class would have between 15 and 19 students.
To recruit them, Minerva is working with guidance counselors and high school principals around the world, Nelson said, and several thousand inquiries have come in via its website from 99 countries.
Courses at Minerva, named for the Roman goddess of wisdom, will be seminar-oriented, focusing on higher level skills such as logic, reasoning, rhetoric and empirical analysis, Nelson said.
Students who need introductory classes such as Economics 101 will be encouraged to find free online lectures.
“Anything that can be delivered in a lecture, we don’t think it’s particularly moral of us to charge money for,” he said.
In a further departure from the traditional educational model, the school’s faculty, projected to be experts in their fields from around the world, will not be offered tenure. They will hold classes with the Minerva students online.
Students will spend their first year in San Francisco and then rotate to other cities in subsequent years, although the locations have not yet been determined.
Minerva is seeking academic accreditation in association with the Keck Graduate Institute, a member of the Claremont University Consortium, according to the school’s website, and Nelson said he hoped to have that in hand before the first class is enrolled.
To get off the ground, Minerva raised $25 million from Benchmark, a top Silicon Valley venture-capital firm, last year. But eventually, Minerva hopes tuition plus fees for room and board will move the for-profit institution into the black.
Larry Summers, a former Treasury Secretary and former president of Harvard University, is an adviser to Minerva; former U.S. Sen. Bob Kerrey is its executive chairman.
Stephen Kosslyn, an academic who headed Stanford University’s Center for Advanced Study in the Behavioral Sciences and previously served as dean of social sciences at Harvard University, is in charge of recruiting faculty.
Minerva is one of several efforts to upend traditional education, largely by using the Internet. Many universities have started offering courses online, often for free. Other groups have adopted the venture-backed model, including Udacity, a service teaching courses in areas such as artificial intelligence and cryptography that was started by a trio of roboticists.
Of course, the glean of the Internet does not guarantee success. Many long-standing online colleges mimic the structure, and sometimes approach the cost, of traditional universities. But some have high dropout and low graduation rates, and employers do not always value their degrees.
via and for more see http://news.msn.com/us/entrepreneur-starts-his-version-of-harvard-tuition-free