The truss ABC shown in the figure supports a horizontal load P1 = 300 lb and a vertical load P2 = 900 lb. Both bars have a cross-sectional area A = 2.4 in2 and are made of steel with E = 30 Ã 106 psi.
(a) Determine the strain energy U1 of the truss when the load P1 acts alone (P2 = 0).
(b) Determine the strain energy U2 when the load P2 acts alone (P1 = 0).
(c) Determine the strain energy U3 when both loads act simultaneously.
30° В Р13300 1b P2 = 900 lb 60 in.
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