From: nospam@de-ster.demon.nl   
      
   Luigi Fortunati  wrote:   
      
   > J. J. Lodder alle ore 18:18:20 del giorno mercoledì ha scritto:   
   > > The simplest way to derive the tides (Earth/Moon only)   
   > > is to calculate the combined potential in co-rotating coordinates.   
   > > (gravity from Earth and Moon, and centrifugal potential   
   > >  from the rotation around their common centre of mass)   
   > >   
   > > It is the shortest way to seeing that there must be two tidal bulges,   
   >   
   > Why does centrifugal force that "appear" ONLY in accelerated references   
   > generate bulges that ALSO appear in inertial references?   
      
   It is a physical effect,   
   so it cannot depend on any particular reference frame.   
   It is just that the derivation is simpler in one frame than in another.   
      
   In non-rotating coordinates you have a dynamic problem   
   rather than a static one, so you have to derive the motions.   
      
   The bulge then comes about because the solid bulk of the Earth   
   falls faster towards the Moon than the water on the far side,   
      
   Jan   
      
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