All Questions
39
questions
1
vote
1
answer
70
views
Tidal forces in the early solar system
I'm reading a book called "Gravity from the ground up" by Bernard Schutz. I don't understand this section from Investigation 13.3 on page 159, which discusses the formation of the solar ...
- 11
0
votes
1
answer
82
views
How to calculate Earth's speed due to moon induced orbit? [closed]
In https://stackoverflow.com/q/75297814/
the answer for the problem was that the earth like the moon had a speed due to the moon induced orbit. I don't understand how this was calculated? I have ...
- 1
1
vote
0
answers
55
views
Moon, Earth and the Sun [closed]
How to prove that the geometric locus of the points where the attractive forces of the Sun and the Moon are of equal intensity is a sphere of radius $ r = \frac{R \sqrt{Mm}}{M-m } $, where $M$ is ...
0
votes
1
answer
327
views
How do the planets stay in their orbit? [duplicate]
The Sun has a strong gravity. The planets also have gravity. So they attract each other. But then why dont they go and mix up with the Sun?
If it is the orbit of the planets or a pre-existing motion ...
- 15
13
votes
3
answers
2k
views
Is it possible for a moon to have the same orbital period as its planet?
Is it possible for a planet to take just as long to orbit its star as a moon takes to orbit the planet? If we assume circular orbits, then
$\text{orbital period}\sim \sqrt{\frac{\text{radius}^{3}}{\...
- 233
-2
votes
3
answers
149
views
Why is the shape of the orbit of the Earth as it is?
My View: I think that if the sun were only force acting on earth (as a centripetal force), the earth would have a circular orbit. Since other planets also exist , there also exists gravitational force ...
- 159
4
votes
2
answers
3k
views
Eccentricity of planets based on distance from Sun
Are the orbits of inner-solar system planets more circular than outer planets? Or is it the other way around? What's the reason for this? We were taught in our high school Physics class that outer ...
- 73
0
votes
1
answer
354
views
How does the Sun's gravity affect the shape of the orbit of the Moon around the Earth?
If we look at the Earth-Moon system as a two-body Keplerian system, we would expect Earth and the Moon to orbit their center of mass (barycenter) in perfect ellipses, with the barycenter at one of the ...
- 307
0
votes
1
answer
271
views
How do I calculate evection and variation for the moon in my simple solar system model?
I am building a model of a simple sun-planet-moon solar system (not the real Sol-Terra-Luna system).
Purpose: to calculate the positions of the sun and moon in the sky of the planet at a given time, ...
- 307
0
votes
0
answers
88
views
Why do Solar Systems form in a disc shape? [duplicate]
This has been asked before, but I still don't get some points about all this.
From what I've gathered so far, it's something like this:
A molecular cloud with some initial spin starts collapsing due ...
- 121
3
votes
2
answers
828
views
Kepler problem: Time spent by a comet inside the orbit of the Earth [closed]
This is was an exercise on my exam of classical mechanics which I couldn't solve. The question goes as follows:
Imagine a comet moving on a parabolic orbit in the plane of the earth. Take the earth's ...
- 65
0
votes
1
answer
259
views
Orbit eccentricity and initial velocity
I was thinking about orbital velocities, and came across this question (Velocity of satellites greater than required velocity). Does the answer to this question imply that for planets going round the ...
- 141
2
votes
2
answers
117
views
Circular trajectories and Kepler's law [duplicate]
I'm studying about the central force and Kepler's law, and I was wondering:
by the first law, the trajectories of planets suppose to be elliptical. but from what I understood, most physical ...
- 315
-4
votes
2
answers
277
views
Is Newton’s gravitation law able to explain the circular motion of the earth around the sun?
I have read in Forbes website that the orbit of the earth around the sun is expanding (by 1.5 cm in 2019).
I have also heard that big bang theory suggests that the universe would collapse into ...
- 127
7
votes
2
answers
2k
views
What are the forces behind the orbit of the Earth around the Sun?
Does the gravity of the sun alone affect the orbit of the earth around the sun?
Look at the image below,(Image is not to scale),
Is it that when earth is going from position 1 to position 2, it ...
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