1. How many equilibrium equations are used in method of sections?
a) 2
b) 4
c) 3
d) 5
Explanation: Moments too can be conserved along with forces in both directions. So, total no. of equations are three.
2. In trusses, a member in the state of tension is subjected to:-
a) push
b) pull
c) lateral force
d) either pull or push
Explanation: Pull is for tension, while push is for compression.
3. In method of sections, what is the maximum no. of unknown members through which the imaginary section can pass?
a) 1
b) 2
c) 3
d) 4
Explanation: Since we have three equilibrium equations, so we can have maximum 3 unknown forces/members through which imaginary section can pass.
4. Method of substitute members is use for which type of trusses?
a) complex
b) compound
c) simple
d) simple and compound
Explanation: Method of substitute members is used to solve problems involving complex trusses.
5. First step to solve complex truss using Method of substitute members is to convert it into unstable simple truss.
a) true
b) false
Explanation: First step is to convert it to stable simple truss.
Shear force is represented by V
Bending moment is represented by M
Distance along the truss is represented by X
W is the uniform load applied.
6. On differentiating V wrt X we will get:-
a) W
b) -W
c) M
d) None of the mentioned
Explanation:On applying equilibrium equation, V – W(x)Δx – V – ΔV = 0
7. On differentiating M wrt X we will get:-
a) W
b) -W
c) V
d) None of the mentioned
Explanation: On applying equilibrium equation, M + VΔx – M – ΔM = 0.
8. If a member of a truss is in compression, then what will be the direction of force that it will apply to the joints?
a) Outward
b) Inward
c) Depends on case
d) No force will be there
Explanation: Member will apply outward force. Joint will in turn apply inward force resulting in compression of the member.
9. Method of the section for determinate truss analysis is time effective.
a) True
b) False
Explanation: Method of the section does not require the calculation of forces in the member prior to it. To compute force in any member, we cut the section and establish equilibrium conditions and hence it is time effective method.
10. To find the forces in the vertical member, preferable equilibrium equations are __________
a) ∑H = 0 & ∑M =0
b) ∑H = 0 & ∑V = 0
c) ∑H = 0, ∑V = 0 & ∑M = 0
d) ∑V = 0 & ∑M = 0
Explanation: Vertical unknowns at a particular selection should be preferably solved for ∑V = 0 first and later for ∑M = 0. Vertical Member does not have possesses any horizontal component of the forces hence ∑H = 0 is irrelevant to the context.