Solve problem without Lagrange Equations.

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In summary, the conversation was about a problem involving the construction of a space station with two identical spherical modules and a mass-less conduit. The question was what the stable orientation of the satellite would be, and a hint was given about the potential energy varying depending on its orientation. The conversation also mentioned using Lagrange equations of motion, but the participants were interested in finding a simpler solution.
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Wondering
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A friend and I were debating the solution to this problem, seen below, and cannot solve it without using Lagrange equations but it is suppose to have a solution that is super simple; but we didn't see it.

Anyway, it is a old qualifier question from the Univ. of Wisconsin (open record so anyone can view it). NOTE: This is NOT a homework question NOR will it appear on another qualifier. My friend and I were simply arguing this:

Homework Statement



Suppose the US and Russia were to jointly build a space station with two identical spherical modules (mass, m) to house their crews, and that they are joined by an effectively mass-less conduit (length, d) for astronauts to visit each other. What is the stable orientation of this satellite? (i.e., determine the angle α between the conduit and the line joining the c.m of the satellite and the Earth’s center). Hint: The potential energy of a non-spherical satellite varies slightly, depending on its orientation relative to its orbit.


Homework Equations


Using general Newtonian Mechanics.


The Attempt at a Solution


The solution we got was very lengthy using Lagrange Equations of motion, we are interested in how anyone could do this a "quick way". Note: We both haven't touched classical mechanics in a long time.
 
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  • #2
Wondering said:
A friend and I were debating the solution to this problem, seen below, and cannot solve it without using Lagrange equations but it is suppose to have a solution that is super simple; but we didn't see it.

Anyway, it is a old qualifier question from the Univ. of Wisconsin (open record so anyone can view it). NOTE: This is NOT a homework question NOR will it appear on another qualifier. My friend and I were simply arguing this:

Homework Statement



Suppose the US and Russia were to jointly build a space station with two identical spherical modules (mass, m) to house their crews, and that they are joined by an effectively mass-less conduit (length, d) for astronauts to visit each other. What is the stable orientation of this satellite? (i.e., determine the angle α between the conduit and the line joining the c.m of the satellite and the Earth’s center). Hint: The potential energy of a non-spherical satellite varies slightly, depending on its orientation relative to its orbit.


Homework Equations


Using general Newtonian Mechanics.


The Attempt at a Solution


The solution we got was very lengthy using Lagrange Equations of motion, we are interested in how anyone could do this a "quick way". Note: We both haven't touched classical mechanics in a long time.

Can you calculate the potential energy of the satellite for horizontal and vertical orientations? What are they?
 

Related to Solve problem without Lagrange Equations.

What is the purpose of solving problems without Lagrange Equations?

The purpose of solving problems without Lagrange Equations is to find alternative methods for solving mathematical and scientific problems that do not rely on the use of Lagrange Equations. This can be useful for simpler or more specialized problems, or for gaining a deeper understanding of the underlying principles involved.

What are some common approaches for solving problems without Lagrange Equations?

Some common approaches for solving problems without Lagrange Equations include direct integration, using numerical methods such as Euler's method or Runge-Kutta methods, and using conservation laws or symmetry principles to simplify the problem.

How do I know when to use Lagrange Equations versus other methods?

The use of Lagrange Equations is most appropriate for solving problems involving multiple degrees of freedom and constraints. If the problem is simpler or has a more specific structure, other methods may be more efficient or effective. Additionally, considering the underlying physical principles involved can also help determine which method is most appropriate.

What are the advantages of solving problems without Lagrange Equations?

Solving problems without Lagrange Equations can offer a deeper understanding of the underlying principles involved, as well as provide alternative solutions that may be more efficient or suited to specific problems. It can also be beneficial for developing problem-solving skills and critical thinking.

Are there any drawbacks to solving problems without Lagrange Equations?

One potential drawback is that alternative methods may not be as generalizable as Lagrange Equations and may not apply to all types of problems. Additionally, they may require more specialized knowledge or techniques, making them less accessible to those without a strong background in mathematics and science.

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