All Questions
Tagged with newtonian-gravity potential
123
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How Can there be a Gravitational Potential when there is NO Gravitational Field? [closed]
How does it make any logic that there exist a potential when there is no net field
for example when we have a Hollow Sphere with mass we can find out the the gravitational *potential inside the sphere ...
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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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2
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Gravitational potential due to arbitrary shape
Outside the uniform sphere, the potential is expressed as if all the masses are concentrated in the center of the sphere.
Is it also true for arbitrary shape?
That is, outside any body, is potential ...
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Converting a gravitation potential from spherical to Cartesian and adding arbitrary tilt
I am working on utilising different potentials in my N-body code to do toy simulations (massless particles in a potential. However, I ran into issues converting a certain potential from a paper into ...
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Defintion of gravitational potential
I am not much clear regarding the defintion of "gravitational potential":
Is the work done for bringing the unit mass from infinity to that point by, gravitaional force or external force? (...
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2
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How much kinetic energy would a star in a galaxy have if it fell to the center?
I want to calculate the speed, or equivalently, the kinetic energy of a star, if it had no rotational speed and fell from a given radius to the center of the galaxy.
I assume Newton's shell theorem ...
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2
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341
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Gravitational potential energy of a galaxy
How can the total gravitational potential energy of a galaxy be calculated?
Lets assume for simplicity that the entire galaxy follows an exponential mass density function for an infinitely small ...
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4
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525
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Interpretation of gravitational waves
A wave has peaks and valleys. I can think of a sine wave as a wave with peaks and valleys.
Now, if gravity is a wave, can we say that gravity would have peaks and valleys, with the valley becoming ...
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Gravitational binding energy of a part of system
I want to calculate the gravitational binding energy of a small central cube (length $l$), which is part of a much larger cube (length L). I have the mass and gravitational potential distribution ...
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What happens if we define the gravitational potential zero point at a finite distance? [duplicate]
Two questions.
Can we, and if so how do we define the gravitational potential of a mass (say the sun) to be zero at a finite distance (say 1 light year)?
How does this change the gravitational force ...
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What energy is transferred into potential? [closed]
This question could be really out of the blue and might receive lots of downvotes, but bugging me quite a time and would appreciate your thoughts easily explained.
We know that when we do work against ...
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106
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Boundary condition of gravitational potential
I solve a system of coupled equations numerically. One of the most important, is equation of the gravitational potential,
$$\nabla^2 \phi = 4\pi G m \rho(r)$$
But I have physical problem with boundary ...
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Gravitational potential and Bessel functions
In electromagnetism, we can solve Laplace and Poisson equation using Bessel functions. But my question is why don't we use Bessel functions to solve these equations for gravitational potential?
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Physical feasibility of zero gravitational potential and non-zero gravitational field
Using $dV/dr = -E$ it is mathematically possible to prove that there exists a point in space where gravitational potential is zero but field is not.
But what is the physical feasibility of the above ...
12
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Gravity vs. EM: action at a distance
Countless texts point to Newton's theory $\nabla^2\phi = 4\pi G\rho$, and remark that the problem here is that a distribution of mass determines the potential instantaneously everywhere, which is ...
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3
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Gravitational potential energy definition
"Gravitational potential energy of a system of masses is defined as the negative of the work done by gravitational force in bringing the masses from infinity to that configuration" ~ the ...
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385
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Gravitational Equipotentials
Can someone explain why the answer is B? I have flaws and inconsistencies within my knowledge.
In terms of how, it lies halfway between the two equipotential lines, so travels a distance of $r/2$, as ...
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Understanding Electric and Gravitational Potentials
I have spent a lot of time trying to understand potentials (gravitational and electrical) and I can't grasp it. I understand that it is the work in bringing a point mass (or charge) from infinity to a ...
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Interpretation of gravitational potential in 2+1D
From Gauss's law of gravity reduced to 2+1 dimensions, one can easily show that the gravitational force follows an inverse law, i.e.
$$
\mathbf{F}(\mathbf{r}) =- \frac{G m M}{|\mathbf{r}|}\hat{\mathbf{...
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159
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How does gravitational potential relate to gravitational acceleration?
I've been wondering about what the gravitational potential V actually tells us, and how it relates to gravitational force and/or acceleration. The formula is $V = -\frac{GM}{r}$. I did some ...
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What is the gravitational potential due to two masses around one point?
Knowing that the formula for gravitational potential is the following.
$$V = -\frac{GM}{r}.$$
We take two masses in between one point let us say T. One mass is m and another 24m. Let us say that the ...
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Trying to understand gravitational force equation
I don't understand the red underlined equations but I understand gravitational force equation in simpler form. Can anyone please explain the equations?
Source
An Introduction to Celestial Mechanics by ...
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239
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Direct calculation of the gravitational potential inside a hollow sphere
I calculated the gravitational potential inside a massive sphere with constant density and got the result:
$$\Phi = -2\pi G\rho R^2 + \frac{2}{3}\pi G\rho R_p^2$$
Where $R$ is the radius of the sphere ...
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Relation Between Gravitational Potential and Acceleration due to gravity
I have always had this question in mind. I know expression for gravitational potential is given as
$$V=-\frac{GM}{r}$$
While acceleration due to gravity is given as
$$g=\frac{GM}{r}$$
So i assume
$$V=-...
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546
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Gravitational field strength between equipotential lines
Is the gravitational field strength between two equipotential lines the same at all distances? For example, in the image, does point P experience the same gravitational field strength as a point ...
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Infinite gravitational potential question
For this question I use Newtonian gravity only. Relativistic gravitational/kinematic effects are ignored.
It is known that the gravity surrounding a point particle of mass $M$ can be described by ...
user324471
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Calculating the gravitational potential of a plane
I'm trying to prove that the potential generated by a infinitesimally thin surface density with constant $\Sigma$ at $z = 0$ is equal to $$\Phi = 2 \pi G \Sigma |z|$$ using Poisson's equation $$\nabla^...
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Why gravitational potential away from a planet increases?
textbooks----
"potential increases towards infinity and is maximum at infinity"
But that is true only when we are seeing potential w.r.t Earth
EXPLANATION---------
So , as we know that ...
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Intuition behind gravitational potential
Gravitational potential at a point is equal to work done in bringing a unit mass from infinity to a particular point
That was the text book definition
$$V_{p} = -\frac{GM}{r}$$
If we calculate $V_p$ ...
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Analytical solution to Poisson's equation for gravity
I am studying Poisson's equation for gravity.
$$\nabla^2 \varphi = 4\pi G\rho$$
I have read that it is solved analytically using some Green's function, to give the well known formula of potential
$$ \...
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