21. If in a pin-jointed plane frame (m + r) > 2j, then the frame is________________?
A. stable and statically determinate
B. stable and statically indeterminate
C. unstable
D. none of the above
✅ The correct answer is option B.
Structural Analysis MCQs
22. The three moments equation is applicable only when___________________?
A. the beam is prismatic
B. there is no settlement of supports
C. there is no discontinuity such as hinges within the span
D. the spans are equal
✅ The correct answer is option C.
23. The Castigliano’s second theorem can be used to compute deflections________________?
A. in statically determinate structures only
B. for any type of structure
C. at the point under the load only
D. for beams and frames only
✅ The correct answer is option B.
24. Number of unknown internal forces in each member of a rigid jointed plane frame is_____________?
A. 1
B. 2
C. 3
D. 6
✅ The correct answer is option C.
25. The width of the analogous column in the method of column analogy is _________________?
A. 2/EI
B. 1/EI
C. 1/2 EI
D. 1/4 EI
✅ The correct answer is option B.
26. The number of independent displacement components at each joint of a rigid-jointed space frame is_______________?
A. 1
B. 2
C. 3
D. 6
✅ The correct answer is option D.
27. A pin-jointed plane frame is unstable if________________?
A. (m + r)<2j
B. m + r = 2j
C. (m + r)>2j
D. none of the above
✅ The correct answer is option A.
28. When a series of wheel loads crosses a simply supported girder, the maximum bending moment under any given wheel load occurs when________________?
A. the centre of gravity of the load system is midway between the centre of span and wheel load under consi-deration
B. the centre of span is midway between the centre of gravity of the load system and the wheel load under consideration
C. the wheel load under consideration is midway between the centre of span and the centre of gravity of the load system
D. none of the above
✅ The correct answer is option B.
29. The fixed support in a real beam becomes in the conjugate beam a___________________?
A. roller support
B. hinged support
C. fixed support
D. free end
✅ The correct answer is option D.
30. If in a rigid-jointed space frame, (6m + r) < 6j, then the frame is_______________?
A. unstable
B. stable and statically determinate
C. stable and statically indeterminate
D. none of the above
✅ The correct answer is option A.