ShmoopTube

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And here's your shmoop du jour brought to you by the Grand Canyon the

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Grand Canyon was created by one River over a super long period of time and [Man looking out onto the Grand Canyon]

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it's considered one of the wonders of the world but we try to dig one hole to

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China when we're seven and well Dad freaks out.. All right, at the Grand [Girl digging a hole in the garden and Dad appears angry]

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Canyon, Max leans over the railing of a beautiful but dangerous vista, his mother

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cries in distress while stepping back from the ledge and his father yelps [Max leaps over the ledge and Mother cries]

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while lunging forward to grab him which of the following was technically true

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for Max as he stands still at the edge of oblivion and here the potential answers

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[Mumbling] All right well

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yeah the Grand Canyon might not be the best place to try and get a closer look [Max jumps down the Grand Canyon]

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at something one mistake and we could see billions of years of history fly

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past but this isn't AP Geology, so let's look at the physics of the Doppler

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effect so the Doppler effect occurs when a wave source is in motion relative to [Boy at the side of the road staring at a car and tortoise]

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an observer if the wave source is approaching the observer the wave

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frequency relative to the observer increases it goes like that if the wave

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source is receding from the observer the frequency will decrease that sounds all

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technical and abstract so let's think of it in real life. Think about being [Boy reading a book]

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stopped at a train crossing as the train approaches the pitch of its horn gets

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higher that's because the sound waves are moving at a higher frequency as the [Train travelling past a parked car]

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train approaches after the train goes by the horn has a lower pitch because the

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waves have a lower frequency as it moves away it was like that we can think of it

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in another way too - Let's say we're playing with our friend Wild Bill - Wild

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Bill has invented a new toy; a ping pong ball machine gun yeah like that the gun [Wild Bill with a ping pong ball machine gun]

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shoots ping pong balls at a rate of one per second... If he stands

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still and shoots ping pong balls at us will get hit once every second he's a [Wild Bill shooting a ping pong ball at a girl]

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good shot, but if he comes charging at us we'll get hit more frequently because the

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distance between us and the source of the ping pong ball will be decreasing so [Wild Bill moves closer to girl and shoots ping pong balls]

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the balls will have less time in the air for every shot and so it makes sense

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that when we finally snap and yell at Wild Bill [Girl shouts at Wild Bill and he runs away]

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making him run away from us we'll get hit less frequently.. Wild Bill's kind of a

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jerk why are we friends with this guy anyway anyway let's get back the Grand

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Canyon. Since Max's Dad is moving toward him the frequency of his voice will increase [Max's Dad runs towards Max and voice frequency increases]

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making the pitch higher so the correct answer is D. Next time we're at the Grand

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Canyon we'll keep our distance from the edge we're not big on heights [Boy scared while standing near the rails of Grand Canyon]

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