Q.
For 1-D bar elements if the structure is having 3 nodes then the stiffness matrix formed is having an order of -
In finite element analysis (FEA), the stiffness matrix represents the relationship between the nodal displacements and forces. For a 1-D bar element, each node typically has one degree of freedom (DOF), which is the axial displacement. Now, let's break it down: 1-D bar element: This type of element resists axial forces, and each node has one degree of freedom for axial displacement. 3 nodes: If the structure consists of 3 nodes, then the total number of degrees of freedom for the system is 3 (one for each node). Stiffness matrix size: The stiffness matrix is a square matrix where the order of the matrix corresponds to the total number of degrees of freedom in the system. Since there are 3 nodes and each node has 1 degree of freedom, the total number of degrees of freedom is 3. Thus, the stiffness matrix will have an order of 3x3 (one degree of freedom per node). The 3x3 matrix will represent the relationship between the forces and displacements at the 3 nodes.
Thus correct option is: B.