Finite Element Methods (global stiffness matrix)

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The discussion focuses on determining the size of the global stiffness matrix K for a 2-D finite element problem. The user calculates the matrix size based on the number of nodes and their degrees of freedom, concluding that for 12 nodes, the matrix is 24 x 24, and for 15 nodes, it is 30 x 30. The methodology emphasizes that the size of the global stiffness matrix is derived from the formula nodes x degrees of freedom. The user seeks confirmation of these calculations and clarification on the approach for exam preparation. Understanding the relationship between nodes and matrix size is crucial for mastering finite element methods.
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Homework Statement


I have the following practice problem which is presented as follows:

What is the size of the global stiffness matrix K (i.e., Kuu) for the 2-D problem?

http://imgur.com/KZec3 (Unsolved)

http://imgur.com/piv1J (Solved)

Homework Equations



The Attempt at a Solution


So in the solved problem which I think I did right I counted the total number of nodes which is 12, since each has 2 degrees of freedom the size of the matrix is 24 x 24? Does this sound correct?

If so now I attempt the other problem, where the ? I think should just be theta's but I believe there was a rendering problem. Anyways my attempt would be again count the number of nodes in which case there are 15 nodes. And again the nodes have a total of 2 degrees of freedom so this is a 30 x 30 size matrix?

Does this sound correct? (there are few problems with which to practice this one, so I'm trying to understand the methodology here for an exam, so any insight would be helpful)
 
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the size of Global stiffness matrix = nodesxnodes.
 

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