Newtons theory of gravity : satelite orbits and ellipses

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Homework Help Overview

The discussion revolves around the application of Newton's theory of gravity in the context of satellite orbits, specifically focusing on two planets of mass m orbiting a star of mass M. The original poster presents an equation related to their orbital dynamics but indicates that their result does not match expectations.

Discussion Character

  • Exploratory, Problem interpretation, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to derive the orbital period using a specific equation but expresses uncertainty about where their reasoning may have gone awry. Other participants question the clarity of the problem setup, particularly regarding the referenced figure.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the problem's details and the original poster's specific goal of finding the orbital period. There is no explicit consensus yet, as questions about the figure and the approach remain open.

Contextual Notes

There is a mention of a figure that is not visible to all participants, which may affect the understanding of the problem. The original poster is specifically looking for the orbital period, but the context of the equations and their derivation is not fully established.

marshall104
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The figure shows two planets of mass m orbiting a star of mass M. The planets are in the same orbit, with radius r, but are always at opposite ends of a diameter.
This is the equation eq. I used:

mv^2/r=GMm/r^2+Gmm/(2r)^2

This is what I came up with but it is not the right answer. Where did I go wrong?

sqrt4pi^2/G(M+m)*r3/2

Any help would be great!
 
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marshall104 said:
The figure shows two planets of mass m orbiting a star of mass M. The planets are in the same orbit, with radius r, but are always at opposite ends of a diameter.
This is the equation eq. I used:

mv^2/r=GMm/r^2+Gmm/(2r)^2

This is what I came up with but it is not the right answer. Where did I go wrong?

sqrt4pi^2/G(M+m)*r3/2

Any help would be great!


What are you trying to find ?
 
marshall104 said:
The figure shows two planets of mass m orbiting a star of mass M.

What figure?

Zz.
 
I'm sorry. I'm trying to find T the orbital period
 

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