TedTest

From the Ted Talk by Asaf Bar-Yosef: An athlete uses physics to shatter world records

Unscramble the Blue Letters

In the elray 1960s, Dick Fosbury tried his hand at almost every sropt, but never eexclled at anything, until, at the age of 16, he turned to the high jump. But when he couldn't cmotpee against the sorntg athletes at his college using the standard high jump teuehcnqis of the time, frsuboy tried to jump a different way: backwards. Instead of jumping with his face towards the bar, bringing each leg over in the traditional satldrde method, he jumped with his back towards the bar. Fosbury ioevprmd his record by over half a foot, and left his coaches amazed by this strange new style of high jumping. During the next few yreas, Fosbury perfected his high jump sylte, won the U.S. National trials, and assured his place in the 1968 ocpylmis in Mexico. In the olimypc Games, Fosbury amazed the world with his new tqnehiuce, wiinnng a gold metal with an Olympic record leap of 2.24 meters. By the next Olympic gmeas, almost all of the competing of high jumpers had aeptdod what came to be known as the Fosbury Flop. What's the secret behind the technique? It lies in a physics concept claeld the center of mass. For every object, we can locate the average position of all of its mass by taking into account how the mass is spread around the object. For instance, the center of mass of a flat, rgaueclntar object of urnfoim density will be in the iostcrnetein of both diagonals, in equal distance from each corner. We can find the center of mass for other objects by similar calculations, or by fnnidig the object's blicanang point, which lies right underneath its center of mass. Try balancing a broom by hdliong it and slowly bringing your hnads together until they meet. This balancing point lies right underneath the broom's center of mass. We humans also have a ctneer of mass. When most ppoele stand up, their center of mass is around the belly, but what happens to your center of mass when you lift your hands in the air? Your center of mass moves upwards. It moves all the time as you move through the day, based on how your body is positioned. It can even move outside of your body. When you bend forward, your center of mass is located below your bent belly in a place where there is no mass at all. Weird to think about, but that's the average position of all your mass. Many objects' center of mass are outside their bodies. Think of doughnuts or brogmnoeas. Now look at the Fosbury Flop, and follow the position of the center of mass of the jumper. The jumper runs very fast, so he can divert his hotizanrol velocity to vcaeitrl velocity, and jumps. Wait for it...there. Look at the jumper's center of mass as his body bends backward. It's below the bar. That is the secret behind the jump. With the old, pre-Fosbury techniques, the jumper had to apply enough force to lift his center of mass above the bar by a few inches in oderr to clear it. The Fosbury Flopper doesn't have to do that. The guneis of the Fosbury Flop is that the jumper can apply the same amount of force, but raise his body much higher than before. That means he can raise the bar so high that even when his center of mass can't go any higher, his arching body can. Fosbury's technique borught the high jump to new heights by sltniitpg the jumper's body away from his center of mass, giving it that much more room to clear higher and hgeihr bars. So the Fosbury Flop may be sports history's only great leap forward, that is also a great leap backward.

Open Cloze

In the _____ 1960s, Dick Fosbury tried his hand at almost every _____, but never ________ at anything, until, at the age of 16, he turned to the high jump. But when he couldn't _______ against the ______ athletes at his college using the standard high jump __________ of the time, _______ tried to jump a different way: backwards. Instead of jumping with his face towards the bar, bringing each leg over in the traditional ________ method, he jumped with his back towards the bar. Fosbury ________ his record by over half a foot, and left his coaches amazed by this strange new style of high jumping. During the next few _____, Fosbury perfected his high jump _____, won the U.S. National trials, and assured his place in the 1968 ________ in Mexico. In the _______ Games, Fosbury amazed the world with his new _________, _______ a gold metal with an Olympic record leap of 2.24 meters. By the next Olympic _____, almost all of the competing of high jumpers had _______ what came to be known as the Fosbury Flop. What's the secret behind the technique? It lies in a physics concept ______ the center of mass. For every object, we can locate the average position of all of its mass by taking into account how the mass is spread around the object. For instance, the center of mass of a flat, ___________ object of _______ density will be in the ____________ of both diagonals, in equal distance from each corner. We can find the center of mass for other objects by similar calculations, or by _______ the object's _________ point, which lies right underneath its center of mass. Try balancing a broom by _______ it and slowly bringing your _____ together until they meet. This balancing point lies right underneath the broom's center of mass. We humans also have a ______ of mass. When most ______ stand up, their center of mass is around the belly, but what happens to your center of mass when you lift your hands in the air? Your center of mass moves upwards. It moves all the time as you move through the day, based on how your body is positioned. It can even move outside of your body. When you bend forward, your center of mass is located below your bent belly in a place where there is no mass at all. Weird to think about, but that's the average position of all your mass. Many objects' center of mass are outside their bodies. Think of doughnuts or __________. Now look at the Fosbury Flop, and follow the position of the center of mass of the jumper. The jumper runs very fast, so he can divert his __________ velocity to ________ velocity, and jumps. Wait for it...there. Look at the jumper's center of mass as his body bends backward. It's below the bar. That is the secret behind the jump. With the old, pre-Fosbury techniques, the jumper had to apply enough force to lift his center of mass above the bar by a few inches in _____ to clear it. The Fosbury Flopper doesn't have to do that. The ______ of the Fosbury Flop is that the jumper can apply the same amount of force, but raise his body much higher than before. That means he can raise the bar so high that even when his center of mass can't go any higher, his arching body can. Fosbury's technique _______ the high jump to new heights by _________ the jumper's body away from his center of mass, giving it that much more room to clear higher and ______ bars. So the Fosbury Flop may be sports history's only great leap forward, that is also a great leap backward.

Solution

adopted
brought
balancing
hands
people
sport
intersection
techniques
rectangular
higher
strong
horizontal
splitting
called
genius
compete
years
early
style
excelled
fosbury
improved
boomerangs
vertical
winning
olympic
finding
technique
order
straddle
center
uniform
games
holding
olympics

Original Text

In the early 1960s, Dick Fosbury tried his hand at almost every sport, but never excelled at anything, until, at the age of 16, he turned to the high jump. But when he couldn't compete against the strong athletes at his college using the standard high jump techniques of the time, Fosbury tried to jump a different way: backwards. Instead of jumping with his face towards the bar, bringing each leg over in the traditional straddle method, he jumped with his back towards the bar. Fosbury improved his record by over half a foot, and left his coaches amazed by this strange new style of high jumping. During the next few years, Fosbury perfected his high jump style, won the U.S. National trials, and assured his place in the 1968 Olympics in Mexico. In the Olympic Games, Fosbury amazed the world with his new technique, winning a gold metal with an Olympic record leap of 2.24 meters. By the next Olympic Games, almost all of the competing of high jumpers had adopted what came to be known as the Fosbury Flop. What's the secret behind the technique? It lies in a physics concept called the center of mass. For every object, we can locate the average position of all of its mass by taking into account how the mass is spread around the object. For instance, the center of mass of a flat, rectangular object of uniform density will be in the intersection of both diagonals, in equal distance from each corner. We can find the center of mass for other objects by similar calculations, or by finding the object's balancing point, which lies right underneath its center of mass. Try balancing a broom by holding it and slowly bringing your hands together until they meet. This balancing point lies right underneath the broom's center of mass. We humans also have a center of mass. When most people stand up, their center of mass is around the belly, but what happens to your center of mass when you lift your hands in the air? Your center of mass moves upwards. It moves all the time as you move through the day, based on how your body is positioned. It can even move outside of your body. When you bend forward, your center of mass is located below your bent belly in a place where there is no mass at all. Weird to think about, but that's the average position of all your mass. Many objects' center of mass are outside their bodies. Think of doughnuts or boomerangs. Now look at the Fosbury Flop, and follow the position of the center of mass of the jumper. The jumper runs very fast, so he can divert his horizontal velocity to vertical velocity, and jumps. Wait for it...there. Look at the jumper's center of mass as his body bends backward. It's below the bar. That is the secret behind the jump. With the old, pre-Fosbury techniques, the jumper had to apply enough force to lift his center of mass above the bar by a few inches in order to clear it. The Fosbury Flopper doesn't have to do that. The genius of the Fosbury Flop is that the jumper can apply the same amount of force, but raise his body much higher than before. That means he can raise the bar so high that even when his center of mass can't go any higher, his arching body can. Fosbury's technique brought the high jump to new heights by splitting the jumper's body away from his center of mass, giving it that much more room to clear higher and higher bars. So the Fosbury Flop may be sports history's only great leap forward, that is also a great leap backward.

Frequently Occurring Word Combinations

ngrams of length 2

collocation	frequency
high jump	4
fosbury flop	3
average position	2
great leap	2

Important Words

account
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age
air
amazed
amount
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arching
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