Vibration related: Rigid body modes

AI Thread Summary
The discussion focuses on analyzing a second degree of freedom system with linear and angular displacements. Participants are asked to clarify the implications of the forcing frequency exceeding the second rigid mode frequency. Understanding this relationship is crucial for determining the spring stiffness and natural frequencies of the system. The significance lies in how it affects the system's response and stability under external forces. Insights into these dynamics can aid in the overall analysis of the rigid body modes.
Doctor_Doom
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Hi, everyone. I'm required to complete an open ended analysis of the following problem:

http://imagefrog.net/show.php/146581_image.png http://imagefrog.net/show.php/146581_image.png I'm not requesting a solution, I'm only looking for assistance in relation to determining the spring stiffness and natural frequencies of the rigid body.

Please explain your understanding of the extract highlighted in the above image. Hence, what is significant about the forcing frequency being greater than the second rigid mode frequency? And how does this assist with determining the spring stiffness or natural frequency of the lumped model.

Please note this is a second degree freedom system, with a linear (up-down) displacement and an angular (about the center of mass) displacement.

Thanks in advance!
 
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