Question

Find out the axial forces in all the members of a truss with loading as shown in fig,

Answer 1

For Equilibrium

∑H = 0; RAH = 15KN

∑V = 0; RAV + RBV = 0

∑MB = 0; RAV X 4 + 10 X 4 + 5 X 8 = 0

RAV = – 20 KN

And RBV = 20KN

Consider ***** A as shown in fig(a)

Consider ***** B as shown in fig (b)

∑H = 0;

– TAB – TBF cos 45 = 0

TBF = – 15/cos 45 = – 21.21KN

TBF = – 21.21KN(C)

∑V = 0

TBC + TBF sin 45 + 20 = 0

TBC – 21.21 sin 45 + 20 = 0

TBC = – 5KN(C)