Answer to Question #179326 in Mechanical Engineering for Aditya

Question

Determine the force in each member of the truss shown. State whether each member is in tension or compression and tabulate the results.

Answer 1

Free body: Entire truss:

+↑ΣF_y = 0: B_y = 0 B_y = 0

+↺ΣM_c = 0: -B_x(3.2 m) - (48 kN)(7.2 m) = 0

B_x = -108 kN B_x = 108 kN ←

+→ΣF_x = 0: C - 108 kN + 48 kN = 0

C = 60 kN C = 60 kN →

Free body: Joint B:

F_AB/5 = F_BC/4 = 108 kN/3

F_AB = 180.0 kN T◀

F_BC = 144.0 kN T◀

Free body: Joint C:

F_AC/13 = F_BC/12 = 60 kN/5

F_AC = 156.0 kN C◀

F_BC = 144 kN (checks)