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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Is Moon's centripetal acceleration balances Earth's gravity?
This may be a repeated question. Using Newton's law of gravitation F= GMm/r^2 , if I substitute the values of mass of earth and moon, distance between earth and moon, I get an value of around 1.9679×...
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If an object falls without friction in a gravitational field, is the average speed independent of the path taken?
If an object falls without friction in a gravitational field, is the average speed independent of the path taken? Consider a marble falling $1 \; m$ in a vacuum under the influence of the Earth's ...
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Conservation of mechanical energy in a vertical spring
Title: Why does mechanical energy appear inconsistent when gravitational potential energy is zero at the bottom of a vertical spring? Body: I'm analyzing a vertical spring-mass system undergoing ...
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Is there a way to think about the 3-body problem by looking at the gravitational field instead of the positions of the objects?
I'm a high school student trying to understand the 3-body problem in a different way. I know the usual method involves solving Newton's equations for how the bodies move over time, but I read that ...
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What force is the tidal force and which force is it? [closed]
1st force - Nuclear Strong Force, 2nd force - Weak Force, 3rd force - EMF, 4th force - gravity, so is this a new force? Where is the math formula to show this is a force of the universe? I didn't see ...
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Contraction in an external gravitational field - collisionless particles vs fluid
I'm studying the behavior of an ideal, self-gravitating fluid under an evolving external gravitational potential (in my case the external potential is a collapsing self-interacting dark matter halo). ...
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What is the optimal orbit for a Dyson swarm?
A solid Dyson sphere is not physically plausible. A more realistic concept is of a Dyson swarm, a huge number of small satellites orbiting a star, completely capturing its emitted energy. Orbits are ...
4votes
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Why do these two equivalent equations give different results for the gravitational potential inside a uniform sphere?
I'm trying to calculate the gravitational potential $\phi(r)$ inside a uniform solid sphere of total mass $M$ and radius $R$. But using different (yet supposedly equivalent) equations gives different-...
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Negative gravity assist of an asteroid belt
I found an (open) exercise asked at undergrad level which reads: Assume that a very high velocity spaceship passes through an asteroid belt with engines off (i.e. there are many asteroids). The ...
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Can the 3-body problem be solved in a 1D simplified case?
The general 3-body problem is well-known to be unsolvable in closed form due to its chaotic nature. However, I am curious about a specific, simplified scenario: If we consider three particles, each ...
1vote
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The direction and speed of end points of two different slides
You have two slides both from same height and end at the same ground level. However one slide drops straight down, the other goes through loops, up and down and twists and turns. Now what is the speed ...
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What happens in perpetual free fall under the Earth's gravity in an expanding universe?
Let's take a universe which contains only the Earth and a rocket. This rocket launches and travels far away from the Earth. Eventually it reaches a point of no return where due to the expansion of the ...
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Very Long Free Falling Rod
My Question Is Whenever A Rod with long height free falling horizontal It's two ends feel two different acceleration because of gravity reduce when we are at height So Point A Have Smaller ...
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1answer
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Escape Velocity Question
How does escape velocity change for launches tangent to the surface of the Earth, rather than perpendicular? This is assuming that the object can travel as fast as necessary to do it and is ...
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Gravity fence at Earth Surface [duplicate]
Whis is Gravity the greatest at Earths surface and less below the surface, and less above the surface and dissipates much quicker above the surface than below? What does this imply, as to the source. ...
