Engineering Mechanics Multiple Choice Questions on “Zero Force Member”.
1. Zero force members has _______ loadings.
a) Infinite
b) No
c) Minimum
d) Maximum
Answer: b
Clarification: The zero member force are having no loadings. They doesn’t involve in the loading part of the story in the trusses. They doesn’t provide the stress nor the strain to the body of the structure. Hence they have no load associated with them.
2. The zero forces are used to improve__________ of the structure.
a) Stability
b) Ductility
c) Malleability
d) Toughness
Answer: a
Clarification: The zero forces increase the stability of the structures. That the frames of the structures, which are there present in the structure. The stability of the joints, making them be in rotational as well as translational equilibrium.
3. Find the force in the member UR.
a) 300N
b) 800N
c) 500N
d) 400N
Answer: c
Clarification: The direction of the unknown is not known to us. To know the direction of the unknown force we take the assumption of it. That is we assume that the particular direction might be the direction of the force and then we do the calculations accordingly. And then we apply the equilibrium equations to the joints.
4. We find the zero force members by inspections.
a) True
b) False
Answer: a
Clarification: The answer is yes. We find the zero force members by inspection. We do not have a special function or any special method for finding the zero force members of the structure. But yes the zero force members are founded by inspections only.
5. If two members of the structure (trusses) form a truss joint and there is no external force acting on that joint then the two members are called___________
a) Scalar form of the force vector
b) The equivalent vector of truss
c) Zero moment member
d) Zero force member
Answer: d
Clarification: If two members of the structure (trusses) forms a truss joint and there is no external force acting on that joint then the two members are called as zero force members. This is again came from inspection. If we imagine the same, we see that there are no movements, thus they are zero force members.
6. Find the horizontal support reactions at A.
a) 300N
b) 0N
c) 500N
d) 400N
Answer: d
Clarification: The direction of the unknown is not known to us. To know the direction of the unknown force we take the assumption of it. That is we assume that the particular direction might be the direction of the force and then we do the calculations accordingly. And then we apply the equilibrium equations to the joints.
7. If two members of the structure (trusses) forms a truss joint and there is an external force acting on that joint then the two members are called as zero force members.
a) False
b) True
Answer: a
Clarification: If two members of the structure (trusses) forms a truss joint and there is no external force acting on that joint then the two members are called as zero force members. This is again came from inspection. If we imagine the same, we see that there are no movements, thus they are zero force members.
8. Which of following is not considered as the true condition for the three members to be zero force members?
a) Any two of the three members must be collinear
b) There must be no external forces acting
c) They should be joined by a joint
d) Any two of the three members must be perpendicular
