With the Winter Olympic Games right around the corner (like, tomorrow today!), sports fans may often wonder how some of the most memorable moments in Olympics and sports history were actually made. For instance, can you answer the following questions?
- How did Olympic greats Bob Beamon (long jump), Greg Louganis (diving) and Katarina Witt (figure skating) achieve their gold medal Olympic records?
- How did Lance Armstrong cycle to a world-beating 5 Tour de France victories?
- How does Beckham actually “bend” a soccer ball?
Dr. Eric Goff, a physics professor at Lynchburg College in Virginia (www.lynchburg.edu), knows the answers to each of these and other questions related to the science of sports. A sports enthusiast, baseball card collector and author of a new book on the topic (“Gold Medal Physics: The Science of Sports”, http://www.publishersweekly.com/article/CA6705660.html?q=goff), Dr. Goff is an expert on analyzing feats of physical prowess and explaining the mechanics and physical dynamics of how some of the greatest moments in sports were made.
If you don’t know the answers, don’t hurt your brain too much…Appomattox News will supply the answers tomorrow afternoon. Stay tuned to this page, where the answers will arrive in an update!
UPDATE from Dr. Eric Goff:
Before answering the above questions, I wish to make something perfectly clear. When physicists like me decide to “explain” how athletes perform the amazing feats which cause our jaws to drop, we do not seek to dehumanize the athletes with a bunch of equations and graphs. Like everyone else, we relish what we observe; only later do we try to enrich our experiences with a deeper understanding of what’s going on.
When thinking about what allows athletes to perform at such high levels, we must keep in mind that athletes are constrained by the same physical laws that constrain the rest of us. Those constraints liberate people like me because I can use those constraints to make predictions about what athletes can do. As an example, imagine standing in place and then jumping straight up into the air. If I know things like your launch speed, the air density, and what your arms and legs are doing, I can calculate how high you will jump. The laws of physics tell me that if you repeat your jump in exactly the same way (or as close as you can), you will jump to the same height each time.
The difference between spectators and professional athletes is the physical conditioning of the athletes and the training they do. LeBron James can’t fly, and he can’t defy the laws of physics. What he can do is launch himself off the ground (or court) with a speed greater than most of the rest of us. That means he stays in the air for a longer time, just as physics says he should.
In my new book, Gold Medal Physics: The Science of Sports (The Johns Hopkins University Press, 2010), I use the setting of sports to teach a little physics. Armed with some knowledge of physics, I take the reader back into the sports world for a closer look at what’s going on. Greg Louganis, Katarina Witt, and Bob Beamon competed in different sports. But the explanation of how they were able to do the amazing things they did is connected to the same law of physics that explains why it’s easier for Lance Armstrong to stay on his bike while he’s riding it compared to trying to stay on it while the bike is not moving. The same law of physics helps explain why it’s wise to give a football a perfect spiral when throwing it.
David Beckham’s bent kicks, Al Oerter’s famed discus throws, and Taiho’s legendary sumo feats are among the myriad of topics in my book. Beckham relies on special air flows around a soccer ball to get it to curve; Oerter needed an incredibly strong arm to pull a discus inward in order to throw it a long way; and Taiho relied on caloric energy that can be traced back to the Big Bang to help him reach the top of the sumo ranks. Whatever the sporting moment, I take the reader gently through the physics with the goal of enriching the reader’s enjoyment of sports.
Here are a few examples:
Greg Louganis: Divers like Louganis approach the end of the springboard in a special way. Using a sequence of steps that cause the board to oscillate in the just the right way, a diver is able to receive energy from the board in such a way that maximizes launch speed off the board. A greater launch speed means more time in the air to execute all the twists and turns necessary for a high score. The constraints put on the diver by the laws of physics tell us that if the diver tries to twist his or her arms in one way, his or her legs need to move in a specified other way. The majesty above the water continues with a low-splash entry into the water. Water drag on the diver slows him or her down quickly enough that the diver is able to return safely to the surface.
Katarina Witt: The iconic image of a figure skater is the fast spin. When Witt dominated skating in the ’80s, she had some amazing spin in her routines. She started by having her arms and one leg as far from the center of her body as possible. Skating on just one leg, Witt would experience a slight rotation. But when she pulled her arms and leg in very close to her body, her rotation speed increased considerably. There is no magic, just the laws of physics! In addition to explaining why Witt and other skaters are able to achieve such high spin rates, my book also discusses why skaters glide so easily on ice.
Bob Beamon: Beamon’s jump in the 1968 Summer Olympics was a legendary feat. He jumped nearly 7 percent farther than any human had ever jumped. Even though he had the maximum allowable tailwind, and even though he was jumping in the high elevations of Mexico City, Beamon’s jump was the perfect storm of maximizing almost every aspect of his jump that was constrained by the laws of physics. He had a great takeoff speed, just a hair shy of the end of the launching board. His powerful abdominal muscles allowed him to throw his arms down and behind him, causing his legs to swing forward, just as physics says they should move. He landed low in the pit with his center of gravity appreciably lower than where it was at the launch. It was truly a Beamonesque moment!
Lance Armstrong: Nobody has ever dominated the Tour de France like Lance Armstrong, winner of seven straight. If we know how much power an elite athlete like Armstrong is able to put out, we can use the laws of physics to predict how long it takes Armstrong to finish a given stage of the Tour de France. To do that, we need to know something about the terrain, the effect of air resistance, the friction between the bike and the road, and how a cyclist’s power gets transferred into getting the bike to go. My book discusses all of these effects and predicts what an elite cyclist can do on a given stage of the Tour de France. Believe it or not, physics helps me predict almost every stage-winning time to better than 10 percent!
David Beckham: Those of us in the U.S. may not like to admit it, but the world’s most popular sport is soccer. Rising to elite status in that sport means world fame, and few soccer players are as famous as David Beckham. That fame is in part due to Beckham’s ability to spin a soccer ball and make it curve. He is known for sending free kicks around defenders and just past the outstretched hands of diving goalies. Like a spinning curveball in baseball or a spinning drive in golf, physics tells us why a spinning soccer ball curves. Air gets whipped around the soccer ball much like water gets deflected by a boat’s turned rudder. The laws of Isaac Newton, now more than three centuries old, tell us why a boat turns and why a soccer ball curves. I show sketches in my book of what the air is doing around a spinning ball.
John Eric Goff was born on September 5, 1970 in Charleston, West Virginia. Falling a tad shy of the talent needed for professional baseball, he turned to a career in physics. His undergraduate degree in physics and mathematics was obtained at Vanderbilt University. He earned a Ph.D. in physics at Indiana University. After a year teaching at Kenyon College and two years teaching at Oberlin College, he obtained a position at Lynchburg College in 2002. He is now chair of the physics department at Lynchburg College. With his wife and two young daughters, he spent the 2008-09 academic year living in Sheffield, England. Working with a colleague at the University of Sheffield, he published novel research dealing with the aerodynamic properties of soccer balls. When not researching, teaching, or spending time with his family, he likes to play and watch sports. He also loves to play bridge.
The link to Dr. Goff’s book leads to Amazon.com, where you can order a copy to answer any other questions you might have about great athletes and the physics that govern performance. Missed it? Here it is again: Gold Medal Physics: The Science of Sports