The 2014 Olympics in Sochi, Russia have begun, and for the past few days I’ve been watching various events with continuous awe. Initially, I was astonished by the sheer athleticism on display, but eventually I started wondering about the physical processes behind it all. How can a figure skater launch his teammate into the air and catch her while moving across the ice? How can speed skaters glide without losing significant velocity to friction? How does a mogul skier, like Canadian champion Alex Bilodeau, make all those twists and turns midair?
Alex Bilodeau’s gold-winning jump. Source: The Guardian.
For those of us who can’t call to mind any explanation for these questions, NBC Learn has provided some answers. They’ve teamed up with the National Science Foundation (NSF) to elucidate some essential physical principles utilized during the Winter Games. The 10 videos on NBC Learn’s website highlight a variety of events, including bobsledding, half pipe, and – in my opinion, the most fascinating sport – slopestyle skiing.
These videos use interviews with both athletes and scientists to illustrate their points. The athletes themselves discuss how they move and react in each event; scientists then go on to explain the detailed principles of these motions in a qualitative way. These complementary perspectives allows the viewer to get a well-rounded, comprehendible idea of the physics surrounding each sport, without getting smothered by scientific jargon. Thus, the Olympics have become a surprising conduit for scientific learning.
Mikael Kingsbury’s arm positions during a jump. Source: Montreal Gazette.
So, based on what NBC Learn has shared on ski jumping, how does Bilodeau execute his aforementioned twists and turns? First, he has to harness enough angular momentum upon taking off to ensure that he can continue spinning mid-air. He does this by twisting his torso and bending his legs, much like a loaded spring. Once he’s made the jump, he can manipulate the orientation of his arms to achieve the desired twists. For instance, lifting one arm up and keep the other down will cause a shift in his centre of mass that will produce a certain degree of twisting, as opposed to keeping both arms down. If he wants to slow his spin in preparation for landing, he can widen his arm span and increase his moment of inertia, thereby decreasing his angular velocity. These procedures, and more, go into making a gold-medal jump.
Physical model of a jump. Source: Wikipedia.
Although I’m still far from constructing a detailed physical model of a slopestyle jump (and even further from actually executing one on the hill), these videos have certainly enlightened me to the applications of some basic laws of physics. It’s amazing that some principles are consistently used among sports; for example, both Bilodeau and figure skater Patrick Chan would know how to alter their moments of inertia with their arms. My unifying outlook after watching the videos is that the utilization of physics’ basic laws are widespread and relevant in even non-academic situations – and it might be worthwhile to expand on these concepts.
If you’re captivated by the Olympics, but have trouble grasping the physical side of the events, definitely check out NBC Learn’s videos. They’re interesting and informative, and you’ll be wiser the next time you cheer on your home team.
Alex Bilodeau’s gold celebration. Source: CTV News.
Sydney Honsberger-Grant
