All ten elements of the truss shown have the same cross sectional area, A-3 in, and...

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All ten elements of the truss shown have the same cross sectional area, A-3 in, and modulus of elasticity, E-30,000 ksi. Use the units of kips and inches to solve all parts of the problem. 1. Draw a free-body diagram of element 6 and show its nodal forces and displacements in the local coordinate system. Find its stiffness matrix in this system. Use the same nomenclatures used in class. Do not use MATLAB in this part. (2 points) 2. Draw a free-body diagram of element 6 and show its nodal forces and displacements in the global coordinate system. Find its stiffness matrix in this system. Use the same nomenclatures used in class. Do not use MATLAB in this part.(4 points) 3. Draw a free-body diagram of joint 6 and find the forces in members 8 and 9 and specify whether they are in tension or compression. Do not use MATLAB in this part.(4 points) 4. Based on the node numbers shown, write a MATLAB code to find (a) the global stiffness matrix for the truss structure by using the direct stiffness method, (12 points), (b) all unknown support reactions and displacements, (4 points), (c) and the normal stress in element 6 and specify whether it is in tension or compression. (4 points) Use the same nomenclatures used in class. pinned 7 H 3 11 ft Node i is the origin of coordinate axes. pinned 12 Pt + 6 Pt 5 J Roller + 12 ft 10 kip 20 kips All ten elements of the truss shown have the same cross sectional area, A-3 in, and modulus of elasticity, E-30,000 ksi. Use the units of kips and inches to solve all parts of the problem. 1. Draw a free-body diagram of element 6 and show its nodal forces and displacements in the local coordinate system. Find its stiffness matrix in this system. Use the same nomenclatures used in class. Do not use MATLAB in this part. (2 points) 2. Draw a free-body diagram of element 6 and show its nodal forces and displacements in the global coordinate system. Find its stiffness matrix in this system. Use the same nomenclatures used in class. Do not use MATLAB in this part.(4 points) 3. Draw a free-body diagram of joint 6 and find the forces in members 8 and 9 and specify whether they are in tension or compression. Do not use MATLAB in this part.(4 points) 4. Based on the node numbers shown, write a MATLAB code to find (a) the global stiffness matrix for the truss structure by using the direct stiffness method, (12 points), (b) all unknown support reactions and displacements, (4 points), (c) and the normal stress in element 6 and specify whether it is in tension or compression. (4 points) Use the same nomenclatures used in class. pinned 7 H 3 11 ft Node i is the origin of coordinate axes. pinned 12 Pt + 6 Pt 5 J Roller + 12 ft 10 kip 20 kips