[ANSWERED] a. Obtain the global stiffness matrix =K of the assemblage shown in Figure P2–1 by superimposing the

a. Obtain the global stiffness matrix =K of the assemblage
shown in Figure P2–1 by superimposing the stiffness matrices of the individual
springs. Here k
1
; k
2
, and k3 are the stiffnesses of the
springs as shown.
b. If nodes 1 and 2 are fixed and a force P acts on node 4
in the positive x direction, find an expression for the displacements of nodes
3 and 4.
c. Determine the reaction forces at nodes 1 and 2.
(Hint: Do this problem by writing the nodal equilibrium
equations and then making use of the force/displacement relationships for each
element as done in the first part of Section 2.4. Then solve the problem by the
direct stiffness method.)