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Waves seawaves

  1. Nov 16, 2004 #1
    i was reading about moon's gravity... talking about how.. moon's gravity influences the waves in some way in the ocean...

    if it does influences the waves... then the moon's gravity should influence us as well....

    what if.. moon is no longer existing..
    how would the waves change and how we live ?
  2. jcsd
  3. Nov 16, 2004 #2


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    The moon causes the tides, it doesn't affect the waves. Losing it wouldn't do much to us.
  4. Nov 16, 2004 #3


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    You would still have waves due to the sun, just smaller.

    Don't know about the "how we live" part.
    Some speculation, I have seen, has it that we would not.
  5. Nov 17, 2004 #4

    Chi Meson

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    As has been noted, the Moon influences the tides. Waves are created primarily by wind. The reason for the moon creating tides is not so much the amount of gravitational force exerted by the moon, but the difference in the moon's gravitational field on the near side and the far side of the earth.

    Since the sun is so far away, there is less of a difference between the sun's gravitational pull on the close side of the earth vs. the garavitational pull on the far side of the earth. THis is why the sun's tidal effects are much smaller than the moon's, even though the sun has a stronger pull on us than the moon does.

    Similarly, there would be no "tidal effect" on you since there is essentially no difference between the moon's pull on your head compared to the moon's pull on your feet.
  6. Nov 17, 2004 #5
    Tidal effects

    Chi provides a good detailed description of the tidal effects the moon has on the Earth.
    What some don't know is that the gravitational pull of the moon on the earth is actually slowing the earth's rotation ever so slightly each year. Hundreds of millions of years ago days were only 18 hours long. Eventually this effect will stop the earth's rotation altogether though this will happen far after other effects terminates life on earth, such as the sun swelling and burning the oceans off :cry: , so don't sweat it. :smile:
  7. Nov 17, 2004 #6


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    This is true.

    However, it would be my understanding that the moon had quite a bit to do with the development of our current biosphere.
    If the moon did not exist the earth would be a different place.
    How much different I don't know.
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