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.
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How does gravity act and propagate in a 2+1D universe?—Newtonian versus general relativity
In a hypothetical 2+1D universe:
if we apply the Newtonian concept of gravity, we might expect that the gravitational force between two mass points with a distance of $r$ would diminish linearly with ...
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Why and How Gravitational mass of a body is affected by the presence of other bodies near it?
My textbook (Cengage Physics, 3rd ed, Mechanics-II, Pg-5.8) says that the gravitational mass of a body is affected by the presence of other bodies near it, whereas the inertial mass of a body remains ...
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Poisson equation and gravitational potential
In Newtonian gravity, what is the difference between the Poisson equation $\Delta\phi =f$ and the expression $\phi = -GM/r$ for the gravitational potential $\phi$? Are both somewhat related?
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Constant speed (at terminal velocity) and zero $g$
I have read the question What would a person experience in a free-falling elevator in a shaft long enough to reach terminal velocity? here and the answer was that you feel exactly the same if the ...
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Why would two different sized bikes not arrive at the same time starting from rest on the same slope?
I was cycling with my little sister who was a little upset by the fact that I would arrive first at the end of a small bridge when we both started from the middle (where the plane is not inclined).
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How do objects reach terminal velocity?
I understand the basics of this principle: the force of gravity acting downward on an object becomes equal to the air resistance acting upward on the object because as the object speeds up, air ...
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How symmetric do we know the gravitation field to be?
Currently, the only ways to measure gravity is on quite large scale. So these experiments measure gravity averaged between vast systems of particles. Of course, such an averaging results¹⁾ in a ...
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Tidal forces in the early solar system
I'm reading a book called "Gravity from the ground up" by Bernard Schutz. I don't understand this section from Investigation 13.3 on page 159, which discusses the formation of the solar ...
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Will a monolayer rise (or sink) in water?
I'm aware of the principles by which an air bubble rises in water . But what happens when a flat monolayer is placed beneath the surface, perfectly perpendicular to local gravity?
Is there still ...
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Would a ball on a long straight plank roll as if it was curved?
If I have an extremely long plank sitting on the surface of the planet (a). If it is sufficiently long, would a ball on the end roll towards the middle as if it were curved (b)?
I'm assuming this ...
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Physics Principle of Balancing Board
Consider one of these
Typically, it is well known that having you legs further apart helps you balance better, the wider the base, the easier it is to balance. I guess a body with a larger base area ...
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Pulling objects from planet's surface by gravity
There is an episode of a TV show I will not name, in which objects from a planet's surface are being pulled into space by a (more or less sudden) high gravitational field. This struck me as ridiculous,...
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Motion of a point particle on a curve under the influence of gravity
Let there be any curve $y=f(x)$. and the coordinates $(x_1,y_1)$ is a point on this curve.
Is it possible that if a particle is released at any $(x_1,y_1)$, it takes the same time $\tau$ to reach $y=0$...
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Is the tidal force at the Roche Limit equivalent to the gravitational force of the body?
There is a pebble on the surface of the earth facing a massive celestial body. If the tidal force becomes equal to 9.81m/s^2, Then it will float.
Would this be at the Roche Limit then?
Does that mean ...
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References on Newton-Cartan Gravity
I'm interested in learning a bit about Newton-Cartan gravity, and I would like some references on the topic. I am already familiar with differential geometry and general relativity, so those could be ...