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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What is the minimum air velocity for a particle to lift vertically?
I'm trying to design a ventilation system for a production room containing cheese powder. If the return air vent is 2 meters above the machine containing the cheese powder, what is the equation for ...
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Is there a deeper relationship between symmetry and gravitational potential comparing Newton's and Einstein's gravity?
In this question, see Why is general relativity in (2+1) dimensions different from cylindrical systems in (3+1) dimensional GR?, it is mentioned
"The gravitational potential Φ of an infinite rod ...
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Escape Velocity from Moon to escape Earth-Moon System
So the escape velocity at Earth is roughly 11.2 km/s, but with the escape velocity of the moon it says that it is 2.38 km/s but since the moon is orbiting the Earth, wouldn't the effective escape ...
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EM 4-potential vs gravity 4-potential?
In classical field theory, the electrostatic and gravitational fields have very similar differential forms:
$$\vec \nabla\cdot \vec{E}=\frac{\rho}{\varepsilon_0}$$
$$\vec \nabla\cdot \vec{g}=-4\pi G\...
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Why do tidal waves appear so suddenly in some rivers?
As tide approaches in lower part of some rivers (e.g. Ganges), a several feet high tidal wave enters from the sea against the flow of the river (making a great noise), and the water level suddenly ...
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Dual of Newtonian gravitational field
In the static state, the laws of Newtonian gravity and Coulomb force have exactly same formulas,
$$F = K \frac{A_1A_2}{r^2}.$$
In the electrical case, moving materials produce a field, say a dual ...
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Why are planets denser as you approach the center?
Gauss' law says that the net electric force inside a hollow, uniform, not rotating sphere is zero. Since gravity is also proportional to the inverse square of the distance, I assume this should apply ...
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Deriving gravitational potential energy using vectors
Here is my attempt at derivation:
First you must find a vector function for the gravitational force.
By the inverse square law, the magnitude of gravitational force between two bodies of mass $m$ ...
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Why is the Moon's gravity so high compared to its mass?
According to Wikipedia, the Moon's mass is about 1.23% of Earth's, but its gravity is 0.1654g or 16.5%. If gravity is proportional to mass, why isn't the Moon's gravity 1.23% of Earth's?
EDIT:
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Why are forces superimposable in Classical Mechanics? Does this also apply in higher theories like General Relativity and Quantum Mechanics?
In classical mechanics, forces are treated as vectors and are added linearly. Is this principle to be treated as an axiom or is there some underlying principle from which this is derived? And given ...
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Is the gravitational potential energy of an object on the ground 0? [duplicate]
In class, we were reviewing kinetic and potential energy and my teacher claimed that on the ground, objects have potential energy. However, as they cannot fall further, isn't their gravitational ...
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Find eccentricity of orbit given the velocity and the semi-major axis
Is it possible to calculate eccentricity of orbit knowing only the semi-major axis and the velocity of both celestial bodies? If not, what other additional information is required.
Does the fact that ...
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What causes gravitational force?
I was thinking that the reason behind the gravitational force is the magma, but after studying Newtonian model of gravity I am confused. It says that there can be gravitational force of attraction ...
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If MOND were true, what would that imply for the geometrical description of gravity as curved spacetime?
As I understand it, Modified Newtonian Dynamics, or MOND (Milgrom M., 1983, ApJ, 270, 365), slightly alters Newton's Law of Gravity by introducing a low acceleration limit below which (for an object ...
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What is G-Force?
Can you explain me what is the G-Force? I always thought it was the force caused by the gravitational acceleration.. But I just saw on myth busters that they calculated the g-force on a belt during a ...
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