Strength of Materials MCQs Set-3

1. A steel beam of length 30 m is fixed between two supports at 8°C with no stress. Find the expansion allowances given if the stress in the bar is to be zero when temperature is raised to 50°C ( α= 12 ×10^-6 per °C, E = 2× 10^5 N/mm^2)

2. The principal stresses σ1, σ2 and σ3 at a point respectively are 80 MPa, 30 MPa and -40 MPa. The maximum shear stress is

3. In a rectangular beam, the maximum shear stress occurs at

4. Slope and deflection at a point in a loaded cantilever beam carrying several loads can be found out by the

5. In a cantilever, maximum deflection occurs, where

6. Rankine's formula for column is valid when slenderness ratio

7. A beam when subjected to an axial pull P

8. A continuous beam is one which is

9. In a rectangular beam, when width, depth and length are doubled, the bending stress

10. The bending moment diagram for a simply supported beam loaded in its centre is

11. Strength of the beam depends on

12. Euler's formula for a mild steel long column hinged at both ends is not valid for slenderness ratio

13. A cantilever beam of square section is subjected to a load W at the free end. If the length of the beam is doubled and the load reduced to half the deflection at the free end compared to original deflection would be

14. The intensity of shear stress in a shaft subjected to torsion is maximum at

15. The nature of stress at the inside surface of a crane hook is

16. If load at the free end of the cantilever beam is gradually increased, failure will occur

17. The shear stress at the centre of a circular shaft under torsion is

18. The bending moment for a certain portion of the beam is constant. For that section, shear force would be

19. The bending moment diagram for a cantilever subjected to a couple M at free end will be

20. The most economical section of the shaft subjected to torsion is

21. A cantilever of length L carries a concentrated load w at the mid span. If the free end is supported on a rigid prop the reaction of the prop will be

22. The bending moment on a section is maximum where shearing force is

23. Bending moment at supports in case of simply supported beam is always

24. The ratio of maximum shear stress to hoop stress in a thin cylindrical pressure vessel is

25. Point of contraflexure in a cantilever of span l, carrying a uniform distributed load, w per metre occurs at

26. The bending moment at the free end of a cantilever beam is

27. Beams of uniform strength are better as compared to beams of uniform cross-section as they are economical

28. The type of stresses setup in a rotating shaft due to torsion are

29. A long column has maximum crippling load when its

30. In a uniform beam supported at one end in position, the maximum stress under self weight of bar shall occur at the

31. A simply supported beam AB of span L carries two concentrated load W each at points L/3 from A and B. What is the shear force in the middle one third portion of beam.

32. A beam of 6 m long, simply supported at its end is carrying a point load W at its mid span. If slope at the end is not to exceed 2°, then deflection at mid span will be

33. The intensity of stress which causes unit strain is called

34. If the bending moment is consistent there will be no______________ stresses