(Solved):   must be correct A truss, shown in Fig. 17.2.5 (a), carries certain vertical load which cau ...

 

must be correct

A truss, shown in Fig. 17.2.5 (a), carries certain vertical load which causes all the tension members to be stressed to \( 230 \mathrm{~N} / \mathrm{mm}^{2} \) and all the compression members to \( 180 \mathrm{~N} / \mathrm{mm}^{2} \). Find the vertical deflection of the panel point \( L_{3} \) if the modulus of elasticity \( E=2.02 \times 10^{5} \) \( \mathrm{N} / \mathrm{mm}^{2} \) (a) F-set of stress under the given loads (b) f-set of forces under unit vertical load at \( L_{3} \)