250+ TOP MCQs on When Assumptions are not Correct and Answers

Structural Analysis Multiple Choice Questions on “When Assumptions Are Not Correct”.

1. Assumptions made regarding various types of joints are always correct.
State whether the above statement is true or false.
a) True
b) False
Answer: b
Clarification: Sometimes these assumptions might not be right due to various unaccounted reasons like friction and external disturbances.

2. In general practice, short roof truss system is:-
a) Unstable
b) Statically determinate
c) Statically indeterminate
d) Provisioned for expansion
Answer: c
Clarification: No, provision is there for expansion on account of short length. Both sides of truss are bolted down making it statically indeterminate.

3. For short roof trusses, what ratio is assumed for load division?
a) 4:1
b) 3:1
c) 2:1
d) 1:1
Answer: d
Clarification: Since short roof trusses are generally statically indeterminate, load distribution is assumed to be in ratio 1:1 on both sides.

4. In type of trusses, provisions are provided for temperature expansion and contraction?
a) Short roof
b) Long roof
c) Short and long roof
d) Neither short nor long roof
Answer: b
Clarification: expansion is not much in short roof trusses as expansion/contraction is proportional to length.

5. Why is base plate provided in short roof trusses?
a) To transmit load effectively
b) For stability
c) For rigidity
d) As provision for temperature related expansion/contraction
Answer: d
Clarification: Base plate is provided on one end of the long roof truss so that it can slide in case of temperature fluctuations.

6. How many possible set of forces does a statically determinate truss has?
a) 0
b) 1
c) 2
d) 3
Answer: b
Clarification: A statically determinate truss has only one set of solution set called unique solution.

7. How many reaction forces are involved in a slotted roller constrained in a cylinder type of joint?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: Two forces act in these type of joints. Force don’t act along the axis of cylinder.

8. How many reaction forces are involved in a ball and socket type of joint?
a) 1
b) 2
c) 3
d) 4
Answer: c
Clarification: One force acts in every three direction.