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 tropical storm showing high winds birtanetg trees and houses, ask yourself, "How did the wind get going so fast?" aamnligzy 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 mtioon. You push on something, and it moves forward. The second type, spin, involves an object rotating, or tnuring on its axis in pacle. An object in straight-line motion will move forever unless something, like the friction of the ground baneteh it, causes it to slow down and stop. The same thing happens when you get something sninipng. 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 gidlnig at the same speed. But if she is spinning on the ice and she pulls her arms in, you know what happens next. She snips fsaetr. This is called the carsivteoonn of angular momentum. mlmeahicatalty, angular munteomm 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 fenird, it will appear to follow a curving path. It doesn't actually cruve, though. It really goes in a sirghatt line. You were the one who was following a cinvrug path, but, from your point of view, the ball aperaps 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 etrah 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 cuold of dust and gas that form the Sun and the Earth and the planets and you and me started to cpaollse as gravity pulled it all together. Before it started to collapse, this cloud had a very gtlnee 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 wmearr at the equator than at the poles. The differences in temperature make differences in air pressure, and the dfinceferes in air purersse make air move. They make the wind blow. But, because the Earth spins, the moving air cuvers to the right in the nrhetron Hemisphere because of the coriolis effect. If there's a region of low pressure in the atmosphere, air is psuehd 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 ulmtleitay came from the spin of the Earth, and the Earth's spin is a rnenamt, a fossil rleic, of the gentle spin of the cloud of dust and gas that collapsed to make the Earth some five billion yreas ago. You are watching something, the spin, that is older than dirt, that's older than rocks, that's oeldr than the Earth itself.
Open Cloze
The next time you see a news report of a hurricane or a tropical storm showing high winds _________ 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 motion. The first is straight-line ______. You push on something, and it moves forward. The second type, spin, involves an object rotating, or _______ on its axis in _____. An object in straight-line motion will move forever unless something, like the friction of the ground _______ 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 _______ at the same speed. But if she is spinning on the ice and she pulls her arms in, you know what happens next. She _____ ______. This is called the ____________ of angular momentum. ______________, angular ________ 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 ______, it will appear to follow a curving path. It doesn't actually _____, though. It really goes in a ________ line. You were the one who was following a _______ path, but, from your point of view, the ball _______ 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 _____ 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 _____ of dust and gas that form the Sun and the Earth and the planets and you and me started to ________ as gravity pulled it all together. Before it started to collapse, this cloud had a very ______ 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 ______ at the equator than at the poles. The differences in temperature make differences in air pressure, and the ___________ in air ________ make air move. They make the wind blow. But, because the Earth spins, the moving air ______ to the right in the ________ Hemisphere because of the coriolis effect. If there's a region of low pressure in the atmosphere, air is ______ 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 __________ came from the spin of the Earth, and the Earth's spin is a _______, a fossil _____, of the gentle spin of the cloud of dust and gas that collapsed to make the Earth some five billion _____ ago. You are watching something, the spin, that is older than dirt, that's older than rocks, that's _____ than the Earth itself.
Solution
- battering
- spinning
- years
- straight
- cloud
- collapse
- warmer
- curve
- relic
- mathematically
- curving
- gentle
- differences
- friend
- appears
- turning
- faster
- pressure
- beneath
- ultimately
- motion
- spins
- gliding
- conservation
- amazingly
- northern
- place
- remnant
- curves
- earth
- older
- momentum
- pushed
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
- air
- amazingly
- angular
- appears
- arms
- atmosphere
- axis
- ball
- battering
- beneath
- bigger
- billion
- billions
- blow
- call
- called
- closer
- cloud
- collapse
- collapsed
- conservation
- cool
- coriolis
- curve
- curves
- curving
- cycle
- day
- daytime
- differences
- dirt
- distance
- drain
- dramatic
- drives
- dust
- earth
- effect
- effects
- equator
- fast
- faster
- follow
- form
- formed
- fossil
- freely
- friction
- friend
- gas
- gentle
- gliding
- gravity
- ground
- hemisphere
- high
- houses
- hurricane
- ice
- inherited
- involves
- line
- mass
- mathematically
- moment
- momentum
- moons
- motion
- move
- moves
- moving
- news
- night
- nighttime
- northern
- number
- numbers
- object
- older
- path
- physics
- place
- planets
- point
- poles
- pressure
- product
- pulled
- pulling
- pulls
- push
- pushed
- rate
- region
- relic
- remnant
- report
- riding
- rocks
- rotating
- showing
- side
- skater
- slow
- slower
- smaller
- speed
- speeding
- spin
- spinning
- spins
- started
- starts
- stop
- stops
- storm
- story
- straight
- sun
- talk
- temperature
- tighter
- time
- toss
- trees
- tropical
- turning
- type
- types
- ultimately
- understand
- view
- warm
- warmer
- watching
- water
- weather
- wind
- winds
- years