ME 270 Solutions for Exam 3

1A. xB = 0 kN yB = 1 kN yC = 3 kN

2A. FBDs

2B. xA = 60 kip y yA = -45 kip F = 45 kip

2C. Load BD = 90 kip Tension

2D. BD = 360,000 psi or 360 ksi

2E. xε in member BD = 0.012 in/in

2F. yε in member BD = -0.0036 in/in

3A. x = 255 MPa 4

xε = 4.5 x 10 m/m

11E = 566 GPa (5.66 x 10 Pa)

3B. y = 271 MPa allow = 180 MPa

3C. ρ = 113 kN

3D. 6 4J = 8.545 x 10 m

a = 17.6 MPa b = 29.3 MPa