Strength of Materials MCQs Set-3

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

2. A continuous beam is one which is

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

4. Strength of the beam depends on

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

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

7. A beam when subjected to an axial pull P

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

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

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

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

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

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

14. 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.

15. 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

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

17. 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)

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

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

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

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

22. In a cantilever, maximum deflection occurs, where

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

24. A long column has maximum crippling load when its

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

26. 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

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

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

29. 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

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

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

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

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

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