Strength of Materials Questions And Answers Objective Type

Strength of Materials MCQ

SET-3

 

61. For a 25 mm hole drilled in plates, the diameter of rivet shank should be

• A. 23mm
• B. 24.5mm
• C. 25mm
• D. 26mm

Answer:  A

62. A beam of uniform strength has

• A. same cross-section throughout the beam
• B. same bending stress at every section
• C. same bending moment at every section
• D. same shear stress at every section

Answer:  B

63. The shear force of a simply supported beam carrying a central point load changes sign at its midpoint.

• A. Correct
• B. Incorrect

Answer:  A

64. In a simple bending theory, one of the assumption is that the material of the beam is isotropic. This assumption means that the

• A. normal stress remains constant in all directions
• B. normal stress varies linearly in the material
• C. elastic constants are same in all the directions
• D. elastic constants varies linearly in the material

Answer:  C

65. The polar modulus for a solid shaft of diameter (D) is

Answer:  B

66. For a 25 mm hole drilled in plates, the diameter of rivet shank should be

• A. 23mm
• B. 24.5mm
• C. 25mm
• D. 26mm

Answer:  A

67. A beam of uniform strength has

• A. same cross-section throughout the beam
• B. same bending stress at every section
• C. same bending moment at every section
• D. same shear stress at every section

Answer:  B

68. The shear force of a simply supported beam carrying a central point load changes sign at its midpoint.

• A. Correct
• B. Incorrect

Answer:  A

69. In a simple bending theory, one of the assumption is that the material of the beam is isotropic. This assumption means that the

• A. normal stress remains constant in all directions
• B. normal stress varies linearly in the material
• C. elastic constants are same in all the directions
• D. elastic constants varies linearly in the material

Answer:  C

70. The polar modulus for a solid shaft of diameter (D) is

Answer:  B

71. The extremeties of any diameter on Mohr’s circle represent

• A. principal stresses
• B. normal stresses on planes at 45°
• C. shear stresses on planes at 45°
• D. normal and shear stresses on a plane

Answer:  B

72. The polar moment of inertia of a hollow shaft of outer diameter (D) and inner diameter (d) is

Answer:  C

73. Two shafts ‘A’ and ‘B’ are made of same material. The shaft ‘A’ is solid and has diameter D. The shaft ‘B’ is hollow with outer diameter D and inner diameter D/2. The strength of hollow shaft in torsion is __________ as that of solid shaft.

• A. 1/16
• B. 1/8
• C. 1/4
• D. 15/16

Answer:  D

74. The bending moment of a cantilever beam of length l and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is __________ at the fixed end.

• A. wl/2
• B. wl
• C. wl2/2
• D. wl2/6

Answer:  D

75. In the below figure, the stress corresponding to point D is

• A. yield point stress
• B. breaking stress
• C. ultimate stress
• D. elastic limit

Answer:  C

76.The Poisson’s ratio for cast iron varies from

• A. 0.23 to 0.27
• B. 0.25 to 0.33
• C. 0.31 to 0.34
• D. 0.32 to 0.42

Answer:  B

77. The Rankine’s theory for active earth pressure is based on the assumption that

• A. the retained material is homogeneous and cohesionless
• B. the frictional resistance between the retaining wall and the retained material is neglected
• C. the failure of the retained material takes place along a plane called rupture plane
• D. all of the above

Answer:  D

78. The strain energy stored in a spring, when subjected to maximum load, without suffering permanent distortion, is known as

• A. impact energy
• B. proof resilience
• C. proof stress
• D. modulus of resilience

Answer:  B

79. An overhanging beam must overhang on both sides.

• A. Correct
• B. Incorrect

Answer:  A

80. The resultant stress on an inclined plane which is inclined at an angle θ to the normal cross-section of a body which is subjected to a direct tensile stress (σ) in one plane, is

• A. σ sin θ
• B. σ cos θ
• C. σ sin 2θ
• D. σ cos 2θ

Answer: B