# Strength of Materials Multiple choice Questions

Posted On:February 2, 2019, Posted By: Latest Interview Questions, Views: 581, Rating :     ## Best Strength of Materials Objective Questions and Answers

Dear Readers, Welcome to Strength of Materials Objective Questions have been designed specially to get you acquainted with the nature of questions you may encounter during your Job interview for the subject of Strength of Materials MCQs. These objective type Strength of Materials questions are very important for campus placement test and job interviews. As per my experience good interviewers hardly plan to ask any particular question during your Job interview and these model questions are asked in the online technical test and interview of many IT & Non IT Industries.

### 1. Modulus of rigidity is defined as the ratio of

a) longitudinal stress to longitudinal strain

b) shear stress to shear strain

c) stress to strain

d) stress to volumetric strain

Ans: b a) -1

b) -0.5

c) 0.5

d) zero

Ans: d

### 3. Limit of proportionality depends upon

a) area of cross-section

c) type of material

d) all of the above

Ans: c

a) 2

b) 3

c) 9

d) 1

Ans: a

a) 0.5

b) 1

c) 2

d) 4

Ans: c

### 6. If all the dimensions of a prismatic bar are doubled, then the maximum stress produced in it under its own weight will

a) decrease

b) remain unchanged

c) increase to two times

d) increase to four times

Ans: c

a) E = 2K(l-2u.)

b) E = 3K(l + u)

c) E = 3K(l-2u)

d) E = 2K(l + u)

Ans: c

a) - 1 and 0.5

b) -land-0.5

c) 1 and - 0.5

d) 0 and 0.5

Ans: a

### 9. The elongation of a conical bar under its own weight is equal to

a) that of a prismatic bar of same length

b) one half that of a prismatic bar of same length

c) one third that of a prismatic bar of same length

d) one fourth that of a prismatic bar of same length

Ans: c

a) homogeneous

b) isotropic

c) elastic

d) orthotropic

Ans: b

a) 7:4

b) 4:7

c) 4:17

d) 16 :49

Ans: a

### If Poisson's ratio of the material is u and longitudinal strain is e, then the final volume of the bar becomes

a) (l + e)(l-u)2V

b) (l-e)2(l + ue)V

c) (l + e)(l-ne)2V

d) (l-ue)3V

Ans: c

a) tension

b) compression

c) shear

d) torsion

Ans: b

### 14. Effective length of a weld is equal to

a) overall length - weld size

b) overall length - throat thickness

c) overall length - 2 x weld size

d) overall length - 2 x throat thickness

Ans: c

### 15. Size of a right angled fillet weld is given by

a) 0.707 x throat thickness

b) 0.414 x throat thickness

c) 2.0 x throat thickness

d) throat thickness

Ans: b

### 16. The effective length of a fillet weld designed to transmit axial load shall not be less than

a) 2 x size of weld

b) 4 x size of weld

c) 6 x size of weld

d) 10 x size of weld

Ans: b

### 17. Size of fillet weld with unequal legs is equal to

a) smaller leg length

b) longer leg length

c) throat thickness

d) average of smaller and longer leg lengths

Ans: a

### 18. Weakest section in a fillet weld is

a) throat of the fillet

b) smaller side

c) side parallel to force

d) side perpendicular to force

Ans: a

### 19. Effective throat thickness of a fillet weld is

a) 0.707 x size of weld

b) 1.414 x size of weld

c) a function of the angle between fusion faces

d) equal to the side of the fillet

Ans: c

a) 6t

b) 6Vt

c) 1.9-y/t

d) 1.5 t+ 4

Ans: b

a) 10

b) 12

c) 15

d) 20

Ans: c

a) 1

b) 2

c) 3

d) 4

Ans: b

a) p,/2

b) p2/2

c) (p,-p2)/2

d) (p, + p2)/2

Ans: d

a)

b) 45°

c) tan"1 (1/2)

d) tan"1 (2)

Ans: b

a) P/A and 45°

b) P/2Aand45°

c) P/2A and 60°

d) P/A and 30°

Ans: b

### 33. The sum of normal stresses is

a) constant

b) variable

c) dependent on the planes

d) none of the above

Ans: a

### 34. The radius of Mohr's circle for two equal unlike principal stresses of magnitude p is

a) p

b) p/2

c) zero

d) none of the above

Ans: a

### 35. Shear stress on principal planes is

a) zero

b) maximum

c) minimum

d) none of the above

Ans: a

### 36. The state of pure shear stress is produced by

a) tension in one direction and equal compression in perpendicular direc-tion

b) equal tension in two directions at right angles

c) equal compression in two directions at right angles

d) none of the above

Ans: a

### 38. According to Rankine's hypothesis, the criterion of failure of a brittle material is

a) maximum principal stress

b) maximum shear stress

c) maximum strain energy

d) maximum shear strain energy

Ans: a

### 39. Maximum bending moment in a beam occurs where

a) deflection is zero

b) shear force is maximum

c) shear force is minimum

d) shear force changes sign

Ans: d

a) shear force

b) deflection

c) slope

Ans: d

### 42. The diagram showing the variation of axial load along the span is called

a) shear force diagram

b) bending moment diagram

c) thrust diagram

d) influence line diagram

Ans: a

### 43. The difference in ordinate of the shear curve between any two sections is equal to the area under

a) load curve between these two sections

b) shear curve between these two sections

c) bending moment curve between these two sections

d) load curve between these two sections plus concentrated loads applied between the sections

Ans: d

a) linear

b) parabolic

c) cubic

d) constant

Ans: c

### 45. The maximum bending moment due to a moving load on a fixed ended beam occurs

a) at a support

b) always at the midspan

d) none of the above

Ans: a

### 46. A cantilever beam AB of length 1 carries a concentrated load W at its midspan C. If the free end B is supported on a rigid prop, then there is a point of contraflexure

a) between A and C

b) between C and B

c) one between A and C and other between C and B

d) nowhere in the beam

Ans: a

a) 0.5

b) 1.0

c) 1.5

d) 2.0

Ans: d

a) 0.2771

b) 0.403 1

c) 0.5861

d) 0.7071

Ans: c

a) 0.2071

b) 0.2111

c) 0.2771

d) 0.251

Ans: b

### 51. A simply supported beam of length 1 carries a load varying uniformly from zero at left end to maximum at right end. The maximum bending moment occurs at a distance of

a) 1/V3 from left end

b) 1/3 from left end

c) 1/V3 from right end

d) 1/3 from right end

Ans: a

### 53. A portion of a beam between two sections is said to be in pure bending when there is

a) constant bending moment and zero shear force

b) constant shear force and zero bending moment

c) constant bending moment and constant shear force

d) none of the above

Ans: a

a) 1/2

b) 1/V2

c) 1/3

d) 2/3

Ans: b

### 55. Of the several prismatic beams of equal lengths, the strongest in flexure is the one having maximum

a) moment of inertia

b) section modulus

c) tensile strength

d) area of cross-section

Ans: b

a) 1.118

b) 1.342

c) 1.000

d) 0.793

Ans: a

a) 150 mm

b) 350 mm

c) 500 mm

d) 550 mm

Ans: d

a) 1 N/mm2

b) 1.125 N/mm2

c) 1.33 N/mm2

d) 1.5 N/mm2

Ans: d

a) 1 N/mm2

b) 1.125 N/mm2

c) 2 N/mm2

d) 2.25 N/mm2

Ans: b

### 62. A prismatic bar when subjected to pure bending assumes the shape of

a) catenary

b) cubic parabola

d) arc of a circle

Ans: d

### 63. A beam of triangular cross section is placed with its base horizontal. The maximum shear stress intensity in the section will be

a) at the neutral axis

b) at the base

c) above the neutral axis

d) below the neutral axis

Ans: c

### 65. A beam of uniform strength has at every cross-section same

a) bending moment

b) bending stress

c) deflection

d) stiffness

Ans: b

### 67. For no torsion, the plane of bending should

a) be parallel to one of the principal axes

b) pass through shear centre of section

c) pass through neutral axis of the section

d) pass through centre of gravity of the section

Ans: b

### 68. Two beams, one of circular cross-section and other of square cross-section, have equal areas of cross-section. If subjected to bending

a) circular section is more economical

b) square section is more economical

c) both sections are equally strong

d) both sections are equally stiff

Ans: b

a) 0.01 d

b) 0.1 d

c) 0.011 d

d) 0.11 d

Ans: c

a) 0 152 1

b) 0.207 1

c) 0.252 1

d) 0.277 1

Ans: a

### 71. A beam ABC rests on simple supports at A and B with BC as an overhang. D is centre of span AB. If in the first case a concentrated load P acts at C while in the second case load P acts at D, then the

a) deflection at D in the first case will be equal to the deflection at C in the second case

b) deflection at C in the first case is equal to the deflection at D in the second case

c) deflection at D in the first case will always be smaller than the deflection at C in the second case

d) deflection at D in the first case will always be greater than the deflection at C in the second case

Ans: a

a) 0.8 m

b) 1m

c) 1.2 m

d) 1.5m

Ans: b

### 75. If the deflection at the free end of a uniformly loaded cantilever beam of length 1 m is equal to 7.5 mm, then the slope at the free end is

d) none of the above

Ans: c

a) 1/2

b) 3/11

c) 5/24

d) 7/41

Ans: d

a) two times

b) four times

c) eight times

d) sixteen times

Ans: c

a) 50%

b) 25%

c) 12.5%

d) 6.25%

Ans: d

### 80. A laminated spring is given an initial curvature because

a) it is more economical

b) it gives uniform strength

c) spring becomes flat when it is subjec-ted to design load

d) none of the above

Ans: c

### 81. A laminated spring is supported at

a) ends and loaded at centre

b) centre and loaded at ends

Ans: b

### 82. Laminated springs are subjected to

a) direct stress

b) bending stress

c) shear stress

d) none of the above

Ans: b

### 83. Deflection in a leaf spring is more if its

a) strength is more

b) strength is less

c) stiffness is less

d) stiffness is more

Ans: c

### 85. Buckling load for a given column depends upon

a) length of column only

b) least lateral dimension only

c) both length and least lateral dimension

d) none of the above

Ans: c

a) P/16

b) P/4

c) P/2

d) 4P

Ans: a

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

a) greater than 80

b) less than 80

c) greater than 180

d) greater than 120

Ans: b

### 88. A long column has maximum crippling load when its

a) both ends are hinged

b) both ends are fixed

c) one end is fixed and other end is hinged

d) one end is fixed and other end is free

Ans: b

a) 10 m

b) 20m

c) 28.28m

d) 40m

Ans: d

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

a) lies between 0 and 140

b) lies between 0 and 100

c)  is less than 80

d)   has any value

Ans: d

a) 31.25

b) 62.5

c) 100

d) 125

Ans: d

### 93. The effect of arching a beam is

a) to reduce bending moment throughout

b) to increase bending moment throughout

c) to increase shear force

d) to decrease shear force

Ans: a

### 94. Internal forces at every cross-section in a arch are

a) nornal thrust and shear force

b) shear force and bending moment

c) normal thrust and bending moment

d) normal thrust, shear force and bending moment

Ans: d

### 95. According to Eddy's theorem, the vertical intercept between the linear arch and the centre line of actual arch at any point represents to some scale

a) bending moment

b) shear force

c) normal thrust

d) deflection

Ans: a

### 96. Due to rise in temperature in a three hinged arch, induced stress is

a) direct compressive

b) direct tensile

c) shear

d) none of the above

Ans: d

### 97. In a three hinged arch, the linear and the actual arch meet at

a) at least three points

b) at least two points

d) nowhere

Ans: a

### 98. If a three hinged parabolic arch carries a uniformly distributed load over the entire span, then any section of the arch is subjected to

a) normal thrust only

b) normal thrust and shear force

c) normal thrust and bending moment

d) normal thrust, shear force and bending moment

Ans: a

### 99. Three hinged arch is

a) statically indeterminate by one degree

b) statically indeterminate by two degrees

c) statically determinate

d) unstable structure

Ans: c

### 101. A linear arch has

a) normal thrust only

b) shear force only

c) bending moment only

d) normal thrust and shear force

Ans: a

### 102. A three hinged arch is carrying uniformly distributed load over the entire span. The arch is free from shear force and bending moment if its shape is

a) circular

b) parabolic

c) elliptical

d) none of the above

Ans: b

a) m = 2j - 3

b) m = 3j-6

c) m > 2j - 3

d) m > 3j - 6

Ans: a

a) triangle

b) rectangle

c) square

d) hexagon

Ans: a

a) one

b) two

c) three

d) four

Ans: b

a) 20 mm

b) 31.25 mm

c) 37.5 mm

d) 42.5 mm

Ans: d

### 125. Proof resilience is the maximum energy stored at

a) limit of proportionality

b) elastic limit

c) plastic limit

d) none of the above

Ans: b

### 126. Strain energy stored in a member is given by

a) 0.5 x stress x volume

b) 0.5 x strain x volume

c) 0.5 x stress x strain x volume

d) 0.5 x stress x strain

Ans: c

a) 10 N.m

b) 25 N.m

c) 50 N.m

d) 100N.m

Ans: c

a) 50 N/mm2

b) 100 N/mm2

c) 200 N/mm2

d) 400 N/mm2

Ans: c

a) 1/4 time

b) 1/8 time

c) 4 times

d) 8 times

Ans: d

### 133. The specimen in a Charpy impact test is supported as a

a)    cantilever beam

b)   simply supported beam

c)   fixed beam

d)   continuous beam

Ans: b

a)   hardness

b)   toughness

c)    strength

d)   creep

Ans: b

a)    creep

b)   fatigue

c)   resilience

d)   plasticity

Ans:

a)    fatigue

b)   creep

c)   plasticity

d)   resilience

Ans: b

### 137. The stress below which a material has a high probability of not failing under reversal of stress is known as

a) tolerance limit

b) elastic limit

c) proportional limit

d) endurance limit

Ans: b

### 138. A three hinged parabolic arch rib is acted upon by a single load at the left quarter point. If the central rise is increased and the shape of arch altered to segmental without changing the other details, the horizontal thrust will

a) increase definitely

b) decrease definitely

c) be difficult to predict

d) increase or decrease depending upon the radius of the segmental arch

Ans: b

### 139. For ductile materials, the most appropriate failure theory is

a) maximum shear stress theory

b) maximum principal stress theory

c) maximum principal strain theory

d) shear strain energy theory

Ans: a

a) 1000 kg/cm2

b) 2000 kg/cm2

c) 2500 kg/cm2

d) 500 kg/cm2

Ans: d

### 141. For the design of a cast iron member, the most appropriate theory of failure is

a) Mohr's theory

b) Rankine's theory

c) Maximum strain theory

d) Maximum shear energy theory

Ans: b