All Questions
164
questions
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Drawing a free-body diagram for a body residing on Lagrange point $L_4$ and $L_5$
I am aware of the fact that Lagrange points $L_4$ and $L_5$ are stable equilibrium points however I cannot understand why they are equilibrium points in the first place.
Consider a Earth-Moon system ...
- 209
2
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3
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50
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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 ...
- 129
1
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2
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180
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Centrifugal force has always been a nightmare to me
Suppose I'm in a rotating space station (that is somewhere in free space) and there is no other force. Now how am I supposed to fall to the circumference of the station if nothing pulls me? I will ...
0
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3
answers
173
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Gravitational force and centre of mass
So question goes like
"What is the magnitude of gravitation force of the particle due to rod?"
In the figure the particle is of mass $m$ and from distance $d$ from end of the rod and the ...
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0
answers
79
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Do all bodies in a 3-body system orbit their center of mass with respect to each of the other bodies?
Scenario
Consider an empty universe with just the Earth, Moon and the Sun. The Earth and the Sun will rotate about their center of mass, which is inside the Sun. The Earth and the Moon will orbit ...
1
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2
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1k
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Centripetal force on the surface of earth
Initially, I was looking for how centripetal force is produced on the surface of the rotating earth for a mass kept at any latitude. I went through the following threads -
Which force provides the ...
- 41
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76
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Two-body problem and motion in a central field
If we consider motion of a body in a central (gravitational) field the equation of motion would be
$$-\frac{\gamma m_1 m_2}{r^2}\frac{\vec{r}}{r}=m_1 \vec{r}^{\prime\prime}$$
where the origin of ...
- 3
0
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2
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72
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How can people be weightless on space station?
I had read it somewhere that on the space station, people are weightless. even though artificial gravity is created there, people are still weightless. how can this be possible if there is gravity, ...
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1
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78
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How does a gas giant planet hold it's spherical shape when it has tidally locked rotation in it's orbit around the Sun?
How does a gas giant planet hold its spherical shape when it has a tidally locked rotation in its orbit around its Sun? Wouldn't it fall apart without its gravitational pull from the rotation? How ...
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How can we use Newton's laws in an accelerating frame? [duplicate]
This question is bothering me for a while. As far as I know, newton's laws are valid for any inertial or non-accelerating frame. Then how can we apply newton's law on earth where we are constantly ...
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1
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91
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Free falling elevator - A person would "levitate"? [duplicate]
If an elevator goes into free fall, assuming there's no friction or anything like that, would it actually float? From what I understand, this would only happen if the elevator falls with an ...
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1
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45
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Why don't we feel centripetal force as we move from the outside of orbit to the inside?
In a debate with a flat earth friend and need help to make sure I understand this correctly.
He points out that the part of earth that is on the outside of its orbit is traveling faster than the ...
1
vote
2
answers
77
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Why is it proclaimed for astronauts to be "falling"?
My physics teacher explained that the reason why it looks like astronauts are floating is because they are "falling". However, the way I think of it is that the outwards inertial force of ...
- 11
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1
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94
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Experiment to find the Center of Gravity under non-uniform $g$-field
When asked about how to find the center of gravity (CG) for a system, the answer normally goes like "suspend the system at different points and see how the vertical lines pass through. The CG is ...
-1
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2
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278
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Equivalence of Center of Inertia and Center of mass [duplicate]
Why does center of gravity and center of mass correspond to the same point on the body only when gravitational field applied can be assumed to be constant?
Reference: IE Irodov, Fundamental laws of ...
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