Questions tagged [newtonian-gravity]
This tag is for questions regarding the Newtonian model of gravity in which the force between two objects is given by $~GMm/r^2~.$ It is a natural phenomenon by which all things with mass or energy – including planets, stars, galaxies, and even light – attract one another. On Earth, gravity gives weight to physical objects, and the Moon's gravity causes the ocean tides.
9 questions from the last 30 days
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Orbiting ring vs orbiting body
A solid ring cannot orbit a mass at its center because it is in unstable equilibrium, and a slight perturbation would cause it to drift.
An object obviously can orbit. You can also take a portion of a ...
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Gravitational field of conic sections and quadrics?
The gravitational field of the infinite rod and infinite plane in 3D are well known, but what about slightly less trivial curves and surfaces? For example, the conic sections and quadrics? Are there ...
- 117
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Are $N$-body perimeters in 2D expected to collapse into a singularity?
Assume a structure of identical unit-mass point particles forming a two-dimensional perimeter (such as a ring), and the only force acting on the structure is the gravitational interaction between the ...
- 52
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On the meaning of the radial coordinate in the simplification of the Two-Body Problem. Inertial or non-inertial reference frame?
When presented with the two-body problems, we usually start from Newton's 2nd equations for the two bodies:
$$
\begin{split}
m_1 \mathbf{\ddot{r}}_1 &= f(r) \mathbf{\hat{r}}, \\
m_2 \mathbf{\ddot{...
- 321
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Q&A: Potential (Energy) and its Sign: inverse square law, comprehensively compiled [closed]
There have been a lot of questions (and I want to highlight a wonderful answer) on the topic of potential energy and its sign, in both the gravitational case and the electrostatic case, about the ...
- 18.2k