[ANSWERED] 1. Evaluate the stiffness matrix for the elements shown in Figure P6–3. The coordinates are in units

1. Evaluate the stiffness matrix for the elements shown in Figure P6–3. The coordinates are in units of inches. Assume plane stress conditions. Let E = 30
10
6
psi, n = 0.25, and thickness t = 1 in.
2.
For the elements given in Problem 6.3, the nodal displacements are given as
Determine the element stresses s
x
; s
y
; t
xy
; s
1
, and s
2
and the principal angle y
p
. Use the values of E; n, and t given in Problem 6.3.