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Sun tides and tidal torque on the earth

  1. Jan 21, 2005 #1

    Andrew Mason

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    It is said that the moon's tidal forces on the earth create differential torque which causes a slowing of the earth rotation. It is said that this causes the moon to increase its radius of orbit. The remarkable result is that rotational energy of the earth is transferred to the moon to increase its gravitational potential. I am not sure how that is accomplished (so far I have not found a convincing explanation of this yet) but lets say it is true.

    Since the sun also exerts a tidal force on the earth, does the sun not cause the earth to slow its rotation as well? If so, what is the earth/sun response to this in order to conserve angular momentum? Does this cause the earth to increase its radius of orbit around the sun, over time?

  2. jcsd
  3. Jan 23, 2005 #2
    This figure gives the scholar traditional explanation for tidal drag and the reason why the moon steals rotational energy from Earth. Source

    However, there are probably several complications, like an increased distance of the moon would decrease it's orbit time and hence it's tidal locked rotation.

    For the sun there is no difference in mechamism, but the forces are considerably weaker.
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