A laminated \([0 / 90 / 0 / 90]_{s}\) carbon/epoxy beam is \(1 \mathrm{~mm}\) thick, \(20 \mathrm{~mm}\) wide, and has \(0.125-\mathrm{mm}\)-thick plies. The lamina properties are

a. Determine the flexural modulus for the beam.

b. How could the flexural modulus be improved without changing the ply materials, the number of plies, or the ply orientations?

c. Using the maximum stress criterion for each ply, determine the magnitude of the maximum allowable bending moment that the beam can withstand. Which ply fails first?

d. What type of analysis would be required if the ply orientations are \([+45 / 90 /-45 / 0]_{s}\) ?

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E = 180 GPa s+) = 1700 MPa E2 10 GPa s = 1400 MPa G12 = 7 GPa s(+) = 40 MPa V12 = 0.28 sf) = 230 MPa