Hi guys. I looking at a vibrations problem with 2 springs in it (System A). I need to find an overall value for the stiffness K to find the natural frequency of the system. I know that normally when 2 springs are in series I should get the sum of (I/Ki)^-1 which would give me an equivilant stiffness of K/2 in this case (System C). But when I take moments about the pivot point og the rod O it makes more sense to me for it to be 2K (System B). Here are some sketches I made.(adsbygoogle = window.adsbygoogle || []).push({});

Can anyone shed some light on this as I'm unsure of which system is correct.

Any help would be greatly appreciated.

Mark.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Which of these spring systems is equivalent?

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