Analysis of 4 Equal Masses on a Circular Path

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The discussion focuses on analyzing a system of four equal masses connected by springs, constrained to move in a circular path. Participants suggest using spherical-polar coordinates to simplify the problem, noting that each mass can be represented by a single angular coordinate, theta. This approach helps in understanding the dynamics of the system, as it differs from traditional one-dimensional mass-spring systems. The challenge lies in finding the normal coordinates and frequencies for the masses in this circular configuration. Overall, the conversation emphasizes the need to adapt methods from linear systems to the complexities of circular motion.
jameson2
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Homework Statement


Given the system of 4 equal masses connected by identical springs, and constrained to move on a circle, find the normal coordinates and frequencies of the masses.

I'm not looking for the answer, just a push in the right direction as I'm having trouble starting. If someone could explain how this is related to the motion of springs and masses in a straight line system, it would be much appreciated.
Even a vague idea would be helpful, thanks.


Homework Equations





The Attempt at a Solution

 
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jameson2 said:

Homework Statement


Given the system of 4 equal masses connected by identical springs, and constrained to move on a circle, find the normal coordinates and frequencies of the masses.

I'm not looking for the answer, just a push in the right direction as I'm having trouble starting. If someone could explain how this is related to the motion of springs and masses in a straight line system, it would be much appreciated.
Even a vague idea would be helpful, thanks.

It's not really related to motions of the mass-spring system in 1D. You might want to consider spherical-polar coordinates with the origin at the center of the circular loop, that way the masses are given by a single coordinate: \theta.
 


I should note that you will actually have 4 \theta coordinates, one for each mass. I hope I didn't introduce any confusion on that.
 
(a) The polarisation pattern is elliptical with maximum (1,1) and minimum (-1,-1), and anticlockwise in direction. (b) I know the solution is a quarter-wave plate oriented π/4, and half-wave plate at π/16, but don't understand how to reach there. I've obtained the polarisation vector (cos π/8, isin π/8) so far. I can't find much online guidance or textbook material working through this topic, so I'd appreciate any help I can get. Also, if anyone could let me know where I can get more...

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