full transcript

From the Ted Talk by Brian Jones: What on Earth is spin?

Unscramble the Blue Letters

The next time you see a news report of a hurricane or a tpacoirl srotm showing high winds battering trees and houses, ask yourself, "How did the wind get going so fast?" anlzmigay enough, this is a motion that started more than five billion years ago. But, to understand why, we need to understand spin. In physics, we talk about two types of miootn. The first is straight-line motion. You push on something, and it moves forward. The second type, spin, involves an object raittnog, or trniung on its axis in place. An oejcbt in straight-line motion will move forever unless something, like the friction of the ground beneath it, causes it to slow down and stop. The same thing happens when you get something sninpnig. It will keep on spinning until something stops it. But the spin can speed up. If an ice skater is gliding across the ice in straight-line motion and she pulls her arms in, she keeps on gliding at the same speed. But if she is spinning on the ice and she pulls her arms in, you know what happens next. She spins faster. This is called the conservation of angular momentum. Mathematically, angular mtenuomm is a pdcuort of two numbers, one that gives the spin rate and one that gives the distance of the mass from the axis. If something is frleey spinning, as one nmbuer gets bigger, the other gets smaller. Arms closer, spin faster. Arms farther, spin slower. Spin causes other effects, too. If you are riding on a spinning merry-go-round and you toss a ball to a friend, it will appear to follow a cvnuirg path. It doesn't actually curve, though. It really goes in a straight line. You were the one who was following a curving path, but, from your point of view, the ball appears to curve. We call this the coriolis effect. Oh, and you are riding on a speeding merry-go-round right now at this very moment. We call it the Earth. The Earth spins on its axis once each day. But why does the Earth spin? Now, that's a story that starts billions of years ago. A cloud of dust and gas that form the Sun and the ertah and the planets and you and me started to collapse as gravity pluled it all together. Before it sarettd to cplasole, this cloud had a very gentle spin. And, as it callspeod, like that ice skater pulling her arms in, the spin got faster and faster. And everything that foermd out of the cloud, the Sun and the planets around the Sun and the moons around the planets, all inherited this spin. And this inherited spin is what gives us nghit and day. And this day-night cycle is what drives our weather. The Earth is warm on the daytime side, cool on the nighttime side, and it's waemrr at the equator than at the poles. The dfncefieres in temperature make differences in air pressure, and the differences in air pressure make air move. They make the wind blow. But, because the Earth spins, the moving air curves to the right in the Northern Hemisphere because of the coriolis efceft. If there's a reiogn of low pressure in the atmosphere, air is pushed toward it, like water going down a drain. But the air cruevs to the right as it goes, and this gives it a spin. With the datimarc low pessrure in a storm, the air gets pulled in thgeitr and tighter, so it gets going faster and faster, and this is how we get the high winds of a hurricane. So, when you see a spinning storm on a wtehaer reropt, think about this: The spin ualtiletmy came from the spin of the Earth, and the Earth's spin is a remnant, a fossil relic, of the gntele spin of the cloud of dust and gas that collapsed to make the Earth some five billion years ago. You are watching something, the spin, that is older than dirt, that's older than rckos, that's older than the Earth itself.

Open Cloze

The next time you see a news report of a hurricane or a ________ _____ showing high winds battering trees and houses, ask yourself, "How did the wind get going so fast?" _________ enough, this is a motion that started more than five billion years ago. But, to understand why, we need to understand spin. In physics, we talk about two types of ______. The first is straight-line motion. You push on something, and it moves forward. The second type, spin, involves an object ________, or _______ on its axis in place. An ______ in straight-line motion will move forever unless something, like the friction of the ground beneath it, causes it to slow down and stop. The same thing happens when you get something ________. It will keep on spinning until something stops it. But the spin can speed up. If an ice skater is gliding across the ice in straight-line motion and she pulls her arms in, she keeps on gliding at the same speed. But if she is spinning on the ice and she pulls her arms in, you know what happens next. She spins faster. This is called the conservation of angular momentum. Mathematically, angular ________ is a _______ of two numbers, one that gives the spin rate and one that gives the distance of the mass from the axis. If something is ______ spinning, as one ______ gets bigger, the other gets smaller. Arms closer, spin faster. Arms farther, spin slower. Spin causes other effects, too. If you are riding on a spinning merry-go-round and you toss a ball to a friend, it will appear to follow a _______ path. It doesn't actually curve, though. It really goes in a straight line. You were the one who was following a curving path, but, from your point of view, the ball appears to curve. We call this the coriolis effect. Oh, and you are riding on a speeding merry-go-round right now at this very moment. We call it the Earth. The Earth spins on its axis once each day. But why does the Earth spin? Now, that's a story that starts billions of years ago. A cloud of dust and gas that form the Sun and the _____ and the planets and you and me started to collapse as gravity ______ it all together. Before it _______ to ________, this cloud had a very gentle spin. And, as it _________, like that ice skater pulling her arms in, the spin got faster and faster. And everything that ______ out of the cloud, the Sun and the planets around the Sun and the moons around the planets, all inherited this spin. And this inherited spin is what gives us _____ and day. And this day-night cycle is what drives our weather. The Earth is warm on the daytime side, cool on the nighttime side, and it's ______ at the equator than at the poles. The ___________ in temperature make differences in air pressure, and the differences in air pressure make air move. They make the wind blow. But, because the Earth spins, the moving air curves to the right in the Northern Hemisphere because of the coriolis ______. If there's a ______ of low pressure in the atmosphere, air is pushed toward it, like water going down a drain. But the air ______ to the right as it goes, and this gives it a spin. With the ________ low ________ in a storm, the air gets pulled in _______ and tighter, so it gets going faster and faster, and this is how we get the high winds of a hurricane. So, when you see a spinning storm on a _______ ______, think about this: The spin __________ came from the spin of the Earth, and the Earth's spin is a remnant, a fossil relic, of the ______ spin of the cloud of dust and gas that collapsed to make the Earth some five billion years ago. You are watching something, the spin, that is older than dirt, that's older than _____, that's older than the Earth itself.

Solution

  1. number
  2. earth
  3. night
  4. freely
  5. report
  6. rotating
  7. weather
  8. turning
  9. collapse
  10. region
  11. spinning
  12. rocks
  13. gentle
  14. tighter
  15. dramatic
  16. ultimately
  17. amazingly
  18. started
  19. motion
  20. tropical
  21. product
  22. pressure
  23. curving
  24. formed
  25. storm
  26. effect
  27. pulled
  28. momentum
  29. object
  30. differences
  31. warmer
  32. curves
  33. collapsed

Original Text

The next time you see a news report of a hurricane or a tropical storm showing high winds battering trees and houses, ask yourself, "How did the wind get going so fast?" Amazingly enough, this is a motion that started more than five billion years ago. But, to understand why, we need to understand spin. In physics, we talk about two types of motion. The first is straight-line motion. You push on something, and it moves forward. The second type, spin, involves an object rotating, or turning on its axis in place. An object in straight-line motion will move forever unless something, like the friction of the ground beneath it, causes it to slow down and stop. The same thing happens when you get something spinning. It will keep on spinning until something stops it. But the spin can speed up. If an ice skater is gliding across the ice in straight-line motion and she pulls her arms in, she keeps on gliding at the same speed. But if she is spinning on the ice and she pulls her arms in, you know what happens next. She spins faster. This is called the conservation of angular momentum. Mathematically, angular momentum is a product of two numbers, one that gives the spin rate and one that gives the distance of the mass from the axis. If something is freely spinning, as one number gets bigger, the other gets smaller. Arms closer, spin faster. Arms farther, spin slower. Spin causes other effects, too. If you are riding on a spinning merry-go-round and you toss a ball to a friend, it will appear to follow a curving path. It doesn't actually curve, though. It really goes in a straight line. You were the one who was following a curving path, but, from your point of view, the ball appears to curve. We call this the coriolis effect. Oh, and you are riding on a speeding merry-go-round right now at this very moment. We call it the Earth. The Earth spins on its axis once each day. But why does the Earth spin? Now, that's a story that starts billions of years ago. A cloud of dust and gas that form the Sun and the Earth and the planets and you and me started to collapse as gravity pulled it all together. Before it started to collapse, this cloud had a very gentle spin. And, as it collapsed, like that ice skater pulling her arms in, the spin got faster and faster. And everything that formed out of the cloud, the Sun and the planets around the Sun and the moons around the planets, all inherited this spin. And this inherited spin is what gives us night and day. And this day-night cycle is what drives our weather. The Earth is warm on the daytime side, cool on the nighttime side, and it's warmer at the equator than at the poles. The differences in temperature make differences in air pressure, and the differences in air pressure make air move. They make the wind blow. But, because the Earth spins, the moving air curves to the right in the Northern Hemisphere because of the coriolis effect. If there's a region of low pressure in the atmosphere, air is pushed toward it, like water going down a drain. But the air curves to the right as it goes, and this gives it a spin. With the dramatic low pressure in a storm, the air gets pulled in tighter and tighter, so it gets going faster and faster, and this is how we get the high winds of a hurricane. So, when you see a spinning storm on a weather report, think about this: The spin ultimately came from the spin of the Earth, and the Earth's spin is a remnant, a fossil relic, of the gentle spin of the cloud of dust and gas that collapsed to make the Earth some five billion years ago. You are watching something, the spin, that is older than dirt, that's older than rocks, that's older than the Earth itself.

Frequently Occurring Word Combinations

ngrams of length 2

collocation frequency
high winds 2
billion years 2
ice skater 2
angular momentum 2
coriolis effect 2
gentle spin 2
air curves 2

Important Words

  1. air
  2. amazingly
  3. angular
  4. appears
  5. arms
  6. atmosphere
  7. axis
  8. ball
  9. battering
  10. beneath
  11. bigger
  12. billion
  13. billions
  14. blow
  15. call
  16. called
  17. closer
  18. cloud
  19. collapse
  20. collapsed
  21. conservation
  22. cool
  23. coriolis
  24. curve
  25. curves
  26. curving
  27. cycle
  28. day
  29. daytime
  30. differences
  31. dirt
  32. distance
  33. drain
  34. dramatic
  35. drives
  36. dust
  37. earth
  38. effect
  39. effects
  40. equator
  41. fast
  42. faster
  43. follow
  44. form
  45. formed
  46. fossil
  47. freely
  48. friction
  49. friend
  50. gas
  51. gentle
  52. gliding
  53. gravity
  54. ground
  55. hemisphere
  56. high
  57. houses
  58. hurricane
  59. ice
  60. inherited
  61. involves
  62. line
  63. mass
  64. mathematically
  65. moment
  66. momentum
  67. moons
  68. motion
  69. move
  70. moves
  71. moving
  72. news
  73. night
  74. nighttime
  75. northern
  76. number
  77. numbers
  78. object
  79. older
  80. path
  81. physics
  82. place
  83. planets
  84. point
  85. poles
  86. pressure
  87. product
  88. pulled
  89. pulling
  90. pulls
  91. push
  92. pushed
  93. rate
  94. region
  95. relic
  96. remnant
  97. report
  98. riding
  99. rocks
  100. rotating
  101. showing
  102. side
  103. skater
  104. slow
  105. slower
  106. smaller
  107. speed
  108. speeding
  109. spin
  110. spinning
  111. spins
  112. started
  113. starts
  114. stop
  115. stops
  116. storm
  117. story
  118. straight
  119. sun
  120. talk
  121. temperature
  122. tighter
  123. time
  124. toss
  125. trees
  126. tropical
  127. turning
  128. type
  129. types
  130. ultimately
  131. understand
  132. view
  133. warm
  134. warmer
  135. watching
  136. water
  137. weather
  138. wind
  139. winds
  140. years