From: goldenfieldquaternions@gmail.com   
      
   On Thursday, July 4, 2019 at 2:18:14 AM UTC-5, Sylvia Else wrote:   
   > On 3/07/2019 5:18 pm, Luigi Fortunati wrote:   
   >> Sylvia Else ha scritto:   
   >>>> So I explicitly ask: is the free fall in a gravitational field inertial   
   >>>> or accelerated?   
   >>>   
   >>> It is inertial, but the only part of your gelatin sphere that is in free   
   >>> fall is the part at its centre of gravity.   
   >>   
   >> The gelatin sphere is ALL in free fall!   
   >>   
   >> Luigi   
   >>   
   >   
   > If the parts of the gelatin sphere were in free fall, then those parts   
   > further from the the body creating the gravitational field would take   
   > longer to orbit than those parts that are closer. But all the parts of   
   > the sphere actually take the same time to orbit, so they cannot all be   
   > in free fall.   
   >   
   > The parts that are not at the centre of gravity of the sphere are being   
   > subject to forces that make them follow orbits that differ from the ones   
   > they'd follow in free fall. Those forces come from the distortion of the   
   > gelatin.   
   >   
   > If the required forces become too great for the gelatin to bear, then   
   > the sphere will break. This is analogous to the situation of a   
   > gravitationally bound object at the Roche limit.   
   >   
   > Sylvia.   
      
   Yes, this is the case, a tidal locked body has these internal   
   forces. Digressing to a Newtonian situation the antipodal points close   
   and far from the main gravitation body both have the same orbital   
   period. Yet Newton or Kepler's 3rd law tells us this is not what happens   
   with orbits. There are then internal forces on this body. This of course   
   has no influence on the orbit of the center of mass. Remember from most   
   elementary mechanics, say Halliday & Resnick level physics, that forces   
   internal to a body generate no net acceleration.   
      
   LC   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)