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The original post in that other thread mentions that BA says "The Earth feels a gravitational pull toward the Sun and a centrifugal force away away from it." That is what my words, in your quotation, is referring to.
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I know but its nice to a have quote from Feynman agreeing with what you have been saying.
Quote:
The centrifugal force on the Earth is the same on the near side as on the far side as well as on the center--so once you make the center of the Earth the reference point, all centrifugal forces are cancelled.
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The centrifugal force is constant, but the tidal force isn't constant and it is the balance of these two 'forces' that defines the behavour. In case when the Earth is falling straight towards the moon the far side is trying to fall a little slower than the near side.
But in the case with the Earth in orbit, the far side moves way from both, the centre of the Earth, and the moon and this is due to the centrifugal force. The tidal force exerted is the same, but the effect is different, (I know its the same in the Earth centre frame of reference, but I think ultimatly you want to explain the effects in an inertial frame)
[img]/phpBB/images/smiles/icon_eek.gif[/img]ops
Thats wrong even in the Earth centre frame you can measure the distance between the far side and the Moon. In the falling case this will dropping quickly and in the orbiting case it will slightly larger than the distance between the Earth centre and the moon plus the radius of the Earth.
Simon
<font size=-1>[ This Message was edited by: SimonCB on 2002-04-02 07:17 ]</font>