Equations of motion for a dual mass-spring-damper

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SUMMARY

The discussion focuses on deriving the equations of motion for a dual mass-spring-damper system, specifically analyzing the positions of two masses represented as q1 and q2. The user initiated the solution by constructing free-body diagrams for each mass and applied Newton's second law, F_net = mq'', to establish the equations governing the system. Concerns were raised regarding the accuracy of the expressions and the signs in the equations, particularly in relation to the extension of the rightmost spring and the force direction from the rightmost damper.

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Homework Statement



We have been given the following mass-spring-damper diagram, and are asked to derive the equations of motion. The positions of the two masses are given as q1 and q2.

upload_2018-10-11_19-6-27.png


The Attempt at a Solution



I began by drawing free-body diagrams for each mass.

upload_2018-10-11_19-8-17.png


Then I set up the equations using F_net = mq'' = sum of the forces acting on the mass.

upload_2018-10-11_19-9-15.png


How does that look? I'm not very experienced at these, and I'm concerned that I've written some of the expressions incorrectly, and that I have some of the signs wrong as well. Thank you.
 

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Think again about the extension of the rightmost spring, and the direction of the force from the rightmost damper.
 

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