Waves

海浪

New Concept English 4, Fluency in English

语言学习

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  • Lesson 40

  • Waves

  • What false impression does an ocean wave convey to the observer?

  • Waves are the children of the struggle between ocean and atmosphere, the ongoing signatures of infinity.

  • Rays from the sun excite and energize the atmosphere of the earth, awakening it to flow, to movement, to rhythm, to life.

  • The wind then speaks the message of the sun to the sea

  • and the sea transmits it on through waves--an ancient, exquisite powerful message.

  • These ocean waves are among the earth's most complicated natural phenomena.

  • The basic features include a crest (the highest point of the wave),

  • a trough (the lowest point), a height (the vertical distance from the trough to the crest),

  • a wave length (the horizontal distance between two wave crests),

  • and a period (which is the time it takes awave crest to travel one wave length).

  • Although an ocean wave gives the impression of a wall of water moving in your direction,

  • in actuality waves move through the water leaving the water about where it was.

  • If the water was moving with the wave,

  • the ocean and everything on it would be racing in to the shore with obviously catastrophic results.

  • An ocean wave passing through deep water causes a particle on the surface to move in a roughly circular orbit,

  • drawing the particle first towards the advancing wave, then up into the wave,

  • then forward with it and then--as the wave leaves the particles behind--back to its starting point again.

  • From both maturity to death, a wave is subject to the same laws as any other 'living' thing.