All Questions
Tagged with newtonian-gravity classical-mechanics
112
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How much time after will two oppositely charged particles collide for both gravitational force and electrostatic force?
Suppose two point objects charged with opposite charges $q_1$ and $q_2$ at a distance $r$ in a vaccum.
So, the net electrostatic force on both objects $= F_c = \frac {q_1q_2}{4π\epsilon_0r²}$ [$\...
- 1,070
-1
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3
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178
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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 ...
- 444
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57
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If the change in potential enegry is equal to the negative of the work done, then this principle isn't consistent here in the case freely falling body
Let us assume that a body of mass $m$ falls from height $h_1$ to $h_2$ :
Here the Work done by gravitational force (Conservative force) is :
$$\mathrm{Force \ ×\ Displacement} = mg \ (h_2-h_1) \tag1$$
...
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What is the effective potential for photons in Newtonian gravity?
I am confused about the movement of photons and their trajectory, I hope you can help me:
What kind of path does light follow in Newtonian gravity?
What is the effective potential for photons in ...
- 1
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3
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224
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Equation of motion of a classic inverted pendulum in free fall
I was thinking in this interesting problem:
Suppose we have this inverted pendulum:
But without this control force $F$ and the system would by loose from a height $h_0$, with initial velocity $0$ ...
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2
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3k
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What happens when the PE equals to zero in the potential energy vs intermolecular distance graph? [closed]
In the potential energy versus inter molecular distance graph, we know that atoms/molecules/particles want to be at optimum distance from each other ie $r_0$ and to the left of this position in the ...
1
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2
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699
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Why in binary star system the 2 bodies revolve around their center of mass?
Can you prove it mathematically?
Is it just an observation?
I know the force between them is $\frac{Gm_1m_2}{r^2}$.
Centripetal force on any one of them is $\frac{mv^2}{r_1}$, where $r_1$ is radius of ...
- 25
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120
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How do you find the position at which three particles obey $m_1 a_1 = m_2 a_2$ if two of the particles form a composite body?
From Classical Mechanics by Kibble:
Consider a system of three particles, each of mass m, whose motion is
described by (1.9). If particles 2 and 3, even though not rigidly bound
together, are ...
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648
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Newton's first law - elevator lift upward and downward force [duplicate]
Why does $F_c$ is equal to $F_g$ and why $F_c$ isn't greater than $F_g$? $F_c$ is moving it upward right, so the force must be greater than gravity to pull it upwards I think.
- 101
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Physical interpretation of the symmetry for the Runge-Lenz vector
In the post What symmetry causes the Runge-Lenz vector to be conserved?, and based on the results of https://arxiv.org/abs/1207.5001, it was it was discussed that the Runge-Lenz vector is the ...
- 3,915
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1k
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When is the effective potential equal to the total energy?
I have a question about the energy of a particle in orbit due to a gravitational attraction. The effective potential given by the gravitational force is defined to be
$$
U_{\text{eff}} = \frac{L^2}{...
- 207
1
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1
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82
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Exact distance travelled by an object due to gravity only
I am aware of the fact that for two point masses in space, the time that it will take for them to collide is, T=$\pi \sqrt{\frac{r_i^3}{8GM}}$, where M is the sum of the 2 bodies' masses, $r_i$ is the ...
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Justification for the nature of planet's orbit in gravitational field!
In kleppner Mechanics in the chapter central force he derived the polar form of orbit for gravitational force as illustrated below: (first two equations are derived from fundamentals of central force)
...
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43
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Variable mass of orbiting body
Considering an object orbiting earth at radius $R$ and speed $v$, at one moment in time the mass of the object starts to decrease, what will happen to the object in terms of speed and orbit?
- 11
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A thought experiment to prove that Newtonian gravity is incomplete [duplicate]
A particle is at rest in one frame having mass $m$. It'll attract another mass proportional to its mass ( newtons law) .
We jump into another frame moving close to speed of light. In this frame it's ...
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