Consider a laminate [±45] of the following material:
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and thickness tk = 0.127 mm, subject to Nx - Ny = 1.0 N/mm. Determine the strength ratio R at the bottom surface of the laminate, using the following strength criteria:
(a) Maximum stress,
(b) Maximum strain,
(c) Interacting failure criterion. Do not adjust for in-situ strength. You are allowed to use a computer program to find the stresses but you must present detailed computations of the R values