Mae Jemison, the first black woman in space.
MAE JEMISON SPEAKS TRUTH
Great ski jumpers are masters of aerodynamics. There are four main parts to a jump: the in-run, take-off, flight, and landing. An athlete’s aerodynamics are most vital in the in-run and, naturally, the flight. During the in-run, the athlete is trying to gain as much speed as possible, so she tucks down and pulls her arms behind her back to streamline her body and keep her frontal area as small as possible. This limits her drag so that she can maximize her speed at take-off. Once in the air, though, the jumpers act like gliders. In flight, there are three forces acting on the the jumper: gravity, lift, and drag. Gravity pulls the jumper down, and drag tends to push her backwards up the hill, but lift, by counteracting gravity, helps keep jumpers aloft for a greater distance. To maximize lift, a jumper angles her skis outward in a V and holds her arms out from her sides. This configuration turns the jumper’s body and skis into a wing. The best jumpers will tweak their positions with training jumps and wind tunnel time to maximize their lift while minimizing their drag in flight and on the in-run. Technique is critical in ski jumping, but conditions play a significant role as well. Tomorrow’s post will discuss why and how judges account for changing conditions. (Photo credits: L. Baron/Bongarts/Getty Images; D. Lovetsky/AP; E. Bolte/USA Today)
FYFD is celebrating the Games with a look at fluid dynamics in the Winter Olympics. Check out our previous posts on the aerodynamics of speed skating, why ice is slippery and how lugers slide so fast.
Team USA: Sochi 2014
Congratulations to Charlie White and Meryl Davis, on becoming the first American ice dancers to win gold! Your performance was inspiring. –Ralph Lauren
Like the athletes who compete on ice, skiers rely on a film of liquid beneath their skis to provide the low friction necessary to glide. The moisture results from the friction of the ski’s base and edges cutting into the snow, and, depending on the conditions of the snow, different surface treatments are recommended for the skis to help control and direct this lubricating film. Similarly, skiers uses various waxes on their skis to lower surface tension and provide additional lubrication. Fluid dynamics can also play a role in tactics for various ski-based events. In endurance events like cross-country skiing, drafting behind other skiers can help an athlete avoid drag and save energy. When drafting, cross-country skiers have lower heart rates. Drag and aerodynamics can also play a significant roles in alpine skiing, especially in speed events like the downhill or super G. In these events solo skiers reach speeds of 125 kph, where drag is a major factor in slowing their descent. Between turns smart skiers will tuck, decreasing their frontal area and reducing drag’s effects. Athletes use wind tunnel testing to dial in their tuck position for maximum effect, and, like speedskaters, skiers may also wear special aerodynamic suits. (Photo credits: F. Cofferini/AFP/Getty Images, C. Onerati; h/t to @YvesDubief)
strippermuffins: YOU HAVE GOT TO WATCH THS FOOTAGE OF JFK. Like I’m not even American, but goodness me. You guys have handsome presidents.THE MUSIC OH MY GOD I’M LAUGHING this is super attractive tho yes THANK YOU FOR SHARING I do agree our presidents are mighty fine.
On the 50th anniversary of his passing, we honor the legacy of President John F. Kennedy. We trace our roots and mission to 1960, when then-Senator Kennedy challenged students at the University of Michigan to serve their country in the cause of peace by living and working in developing countries. His inspiration led to the establishment of this agency in 1961 with a mission to promote world peace and friendship.
Today, we are more vital than ever, working in collaboration with public and private partners in emerging and essential areas such as education, information technology, agriculture and environment, and business development in countries around the world. The Peace Corps is committed to giving all Americans who want to serve the opportunity to make a difference and bring their experience back home to enrich their communities here in the United States.
Since 1961, more than 215,000 Americans of all ages and backgrounds have responded to Kennedy’s enduring challenge, demonstrating how the power of an idea can capture the imagination of an entire nation.
Sunset in Tuscany
tribute to several people:
- Wesley Willis
- Henry Darger
- Yago Hortal
- Angelo Franco
People I could never hold a candle to but who inspire me to play around.