Question

Number of zero force members in the truss shown below is

• A. 8
• B. 7
• C. 6
• D. 9

Answer 1

The correct option is B 7

At joint F: No force acting at joint F, therefore, force in member EF and FM are zero.
At joint M: $P_4$ is in the same direction as of member EM, therefore, force in LM is zero.
At joint K: Members JK and KL are in line with each other, therefore force in member KD is zero.
At joint C: Member CD and CB are in line with each other, therefore force in member CJ is zero.
At joint H: Member HG and HI are in line with each other, therefore, force in member HB is zero.
At point A: Force $P_1$ is in the same direction as of member AB, therefore, force in member AG is zero.
$\therefore$ Zero force members are EF, FM,LM, KD, CJ, HB and AG.