1. What is the maximum number of members a truss can have for a given number of joints,
according to the stability equation?
A. 2j - 3
B. 3j - 2
C. j - 3
D. 3j
Answer: A) 2j - 3
Rationale: For a truss to be stable, the number of members (m) must satisfy the equation
m=2j−3m = 2j - 3m=2j−3, where jjj is the number of joints in the truss.
2. When analyzing a truss using the method of joints, which of the following is a basic
assumption?
A. All joints are perfectly rigid
B. All loads are concentrated at the joints
C. Members are only subject to axial forces
D. Each joint can rotate independently
Answer: C) Members are only subject to axial forces
Rationale: The method of joints assumes that truss members are idealized as being subjected
only to axial forces (tension or compression), ignoring bending and torsion.
,3. What does the "zero-force member" rule in trusses indicate?
A. A member is under no load
B. A member is not connected to any joint
C. A member does not carry any internal force in certain conditions
D. A member is always under tension
Answer: C) A member does not carry any internal force in certain conditions
Rationale: Zero-force members are determined by looking at joints with two non-collinear
members and no external load or reaction. These members do not carry internal force under these
conditions.
4. In a simple truss, how many reactions can be expected at the supports?
A. 1
B. 2
C. 3
D. 4
Answer: B) 2
Rationale: A simple truss typically has two reactions at the supports—one vertical and one
horizontal (depending on the support conditions).
5. Which of the following is used to calculate the deflection of a truss?
, A. Mohr’s Circle
B. Superposition principle
C. Timoshenko beam theory
D. Truss stiffness matrix
Answer: B) Superposition principle
Rationale: The superposition principle is often used to calculate deflections in trusses by
considering the effect of individual forces or moments on the structure.
6. In the method of joints, if a joint is subjected to two non-collinear external forces and no
external moments, what is the number of unknown forces?
A. 0
B. 1
C. 2
D. 3
Answer: B) 1
Rationale: At a joint with two non-collinear external forces, there is only one unknown force to
solve for, which is the internal force in one of the truss members.
7. What is the primary purpose of a truss in structural design?
A. To increase the strength of the structure
B. To support the roof and floor loads
according to the stability equation?
A. 2j - 3
B. 3j - 2
C. j - 3
D. 3j
Answer: A) 2j - 3
Rationale: For a truss to be stable, the number of members (m) must satisfy the equation
m=2j−3m = 2j - 3m=2j−3, where jjj is the number of joints in the truss.
2. When analyzing a truss using the method of joints, which of the following is a basic
assumption?
A. All joints are perfectly rigid
B. All loads are concentrated at the joints
C. Members are only subject to axial forces
D. Each joint can rotate independently
Answer: C) Members are only subject to axial forces
Rationale: The method of joints assumes that truss members are idealized as being subjected
only to axial forces (tension or compression), ignoring bending and torsion.
,3. What does the "zero-force member" rule in trusses indicate?
A. A member is under no load
B. A member is not connected to any joint
C. A member does not carry any internal force in certain conditions
D. A member is always under tension
Answer: C) A member does not carry any internal force in certain conditions
Rationale: Zero-force members are determined by looking at joints with two non-collinear
members and no external load or reaction. These members do not carry internal force under these
conditions.
4. In a simple truss, how many reactions can be expected at the supports?
A. 1
B. 2
C. 3
D. 4
Answer: B) 2
Rationale: A simple truss typically has two reactions at the supports—one vertical and one
horizontal (depending on the support conditions).
5. Which of the following is used to calculate the deflection of a truss?
, A. Mohr’s Circle
B. Superposition principle
C. Timoshenko beam theory
D. Truss stiffness matrix
Answer: B) Superposition principle
Rationale: The superposition principle is often used to calculate deflections in trusses by
considering the effect of individual forces or moments on the structure.
6. In the method of joints, if a joint is subjected to two non-collinear external forces and no
external moments, what is the number of unknown forces?
A. 0
B. 1
C. 2
D. 3
Answer: B) 1
Rationale: At a joint with two non-collinear external forces, there is only one unknown force to
solve for, which is the internal force in one of the truss members.
7. What is the primary purpose of a truss in structural design?
A. To increase the strength of the structure
B. To support the roof and floor loads
