Posted: Jan 02, 2015 4:03 pm
DavidMcC wrote:How can the equatorial ocean bulge not be relevant to gravity variation, since it is tipped up from the equator mainly by the gravitational pull of the moon
Because they are totally separate effects. There's a standing effect from the rotation of the Earth and a separate effect from the tides. If there was no moon there would still be a an equatorial bulge, but no lunar tide. If the Earth was not rotating there would be no equatorial bulge, but there would still be a lunar tidal change in surface gravity, with reductions on the points closest to and furthest away from the moon.
This is however, still changing the subject away from your misunderstanding, which is that without the Earth's rotation around its axis the weight experienced on the far side of the Earth would increase, when in reality it would still decrease.