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[ti:Waves]
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[00:01.54]Lesson 40
[00:03.21]Waves
[00:10.91]What false impression does an ocean wave convey to the observer?
[00:17.55]Waves are the children of the struggle between ocean and atmosphere, the ongoing signatures of infinity.
[00:26.32]Rays from the sun excite and energize the atmosphere of the earth, awakening it to flow, to movement, to rhythm, to life.
[00:36.58]The wind then speaks the message of the sun to the sea
[00:40.58]and the sea transmits it on through waves--an ancient, exquisite powerful message.
[00:48.64]These ocean waves are among the earth's most complicated natural phenomena.
[00:54.50]The basic features include a crest (the highest point of the wave),
[00:59.77]a trough (the lowest point), a height (the vertical distance from the trough to the crest),
[01:07.89]a wave length (the horizontal distance between two wave crests),
[01:13.45]and a period (which is the time it takes awave crest to travel one wave length).
[01:19.92]Although an ocean wave give the impression of a wall of water moving in your direction,
[01:25.99]in actuality waves move through the water leaving the water about where it was.
[01:32.43]If the water was moving with the wave,
[01:35.08]the ocean and everything on it would be racing in to the shore with obviously catastrophic results.