Factor of Safety for Member (1)  
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The figure shows the free body diagram of the beam. The reaction forces at C are C subscript x and C subscript y directed horizontally to the right and vertically upwards respectively. A 75 kilo newton load acts on the beam 2.5 meters from point C. The force along the support rod directed away from the point B is F subscript 1 at an angle of 35 degrees with the horizontal.
The axial force in member (1) is
F1=-65.38 kN,
the cross-sectional area is
A1=3.080 mm2,
and the limiting stress is 50 MPa.
Compute the normal stress:
σ1=F1A1=(-65.38 kN)(1,000 N/kN)3.080 mm2
=-21.23 MPa=21.23 MPa (C)
The factor of safety for member (1) is therefore:
FS=50 MPa21.23 MPa=2.36