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Quick (Most likely simple) Question

  1. Mar 23, 2007 #1
    I was just curious why the moon has a pull on a tide facing the moon and on the complete opposite side of the earth it has the same pull.

  2. jcsd
  3. Mar 23, 2007 #2
    Actually the mass of the moon causes the earth to squeeze a bit.
  4. Mar 24, 2007 #3


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    Hi Josh! Welcome to these Forums!

    One way of looking at it is to say on the Moon's side of the Earth the Moon pulls the ocean away from the Earth, on the other side the Moon pulls the Earth away from the ocean.

    Another way of understanding it is to consider a sphere of dust particles, as a model of a 'fluid' Earth, falling towards the Moon. The 'left' and 'right' extremities are drawn towards the Moon and therefore close in on each other.

    The sphere becomes an oblate spheroid because of the slightly different directions in which the Moon attracts different parts of the Earth. These are called tidal forces and are described both by Newtonian gravitation and General Relativity.

    I hope this helps.

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