A paradox inside Newtonian world

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    Newtonian Paradox
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The discussion revolves around a paradox in Newtonian mechanics concerning gravitational forces and the behavior of masses. Participants debate the calculations and assumptions regarding how gravitational forces act on a system of masses arranged in a specific configuration. Key points include the assertion that the net force on certain masses is directed leftward, while others argue that the center of mass may not actually move left due to the dynamics of the system over time. The conversation highlights the complexities of infinite mass distributions and the implications for conservation laws in physics. Ultimately, the paradox challenges traditional interpretations of gravitational interactions in a Newtonian framework.
  • #511
Yes because the force on the center of mass will be equal to the sum of the forces on all particles in the system. Thus the forces add to be infinite. This is a problem.
 
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  • #512
First of all, the force to the mass center is NOT the sum of all forces. Not at all.

Do you know that?
 
  • #513
Tomaz Kristan said:
First of all, the force to the mass center is NOT the sum of all forces. Not at all.

Do you know that?
It hadn't occurred to us.

M\mathbf{R} = \sum_i m_i \mathbf{r}_i
M\dot{\mathbf{R}} = \sum_i m_i \dot{\mathbf{r}_i}
M\ddot{\mathbf{R}} = \sum_i m_i \ddot{\mathbf{r}_i}
 
  • #514
Do you know, that this is not the case?

You and I could be forced to accelerate in the opposite directions, yet the center of the mass of the you&me system, would not move at all. Let alone to be accelerated.

Just one example.
 
  • #515
This thread has gone long enough, and I believe that nothing has been achieved. This topic is now closed, and no new ones should be opened related to it.

Zz.
 

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