# Strength of materials (SOM)

## ME3I

### 22306

#### Multiple Choice Questions (MCQs)

Go To Part01/Part 02

##### Part 01
1   The Poisson’s ratio is equal to
(A)   Lateral Strain /Longitudinal Strain
(B)   Longitudinal Strain / Lateral Strain
(C)   Longitudinal Strain x Lateral Strain
(D)   None of the above

2   According to Hook’s law, within elastic limit, stress is
(A)   inversely proportional to strain
(B)   directly proportional to strain
(C)   does not depend on strain
(D)   None of the above

3   The Young’s modulus of elasticity of a material is 2.5 times its modulus of rigidity. The Poisson’s ratio for the material will be,
(A)   0.25
(B)   0.33
(C)   0.50
(D)   0.75

4   For a given applied load, induced stress is a function___
(A)   type of material of the body
(B)   cross section area of the body
(C)   both type of material and cross section of the body
(D)   None of the above

5   If a material expands freely due to heating, it will develop
(A)   Thermal stress
(B)   Tensile stress
(C)   Compressive stress
(D)   No stress

6   The stress induced in a body when suddenly loaded is ________ the stress induced when the same load is applied gradually.
(A)   equal to
(B)   twice
(C)   one-half
(D)   four times

7   The thermal stress is a function of:
(A)   Coefficient of linear expansion
(B)   Temperature rise
(C)   Modulus of elasticity
(D)   All of the above

8   The energy stored in a body when strained within elastic limit is known as
(A)   strain energy
(B)   potential energy
(C)   impact energy
(D)   proof resilience

9   The highest point on stress-strain diagram is called ____
(A)   Yield point
(B)   Ultimate point
(C)   Fracture point
(D)   Proportional limit

10   Member connected in series subjected under certain external load , total deformation is the___
(A)   Product of all deformation
(B)   Sum of all deformation
(C)   Maximum deformation from all deformation
(D)   None of the above

11   The moment of inertia of a circular section having 2 cm diameter about its diameter is _____mm4
(A)   1.5708
(B)   0.7854
(C)   7853.9
(D)   15707.9

12   Parallel axis theorem is used for transfer of MI from _______axis to any other parallel coplanar axis.
(A)   any vertical
(B)   any horizontal
(C)   centroidal
(D)   None of the above

13   The moment of inertia of quarter circle having radius ‘R’ about its centroidal axis is
(A)   0.11R4
(B)   0.055R4
(C)   0.22R4
(D)   0.35R4

14   The moment of inertia of a triangular area having base 20mm and height 60mm about its centroidal axis is_____mm4
(A)   36 x 104
(B)   12 x 104
(C)   18 x 104
(D)   9 x 104

15   For a particular figure, if Ixx = 20 mm4 , Izz = 60 mm4 , then Iyy will be ____
(A)   80 mm4
(B)   40 mm4
(C)   3 mm4
(D)   30 mm4

16   The moment of inertia of a square section of size 1 unit about its diagonal is
(A)   1/3
(B)   1/4
(C)   1/12
(D)   1/6

(A)   one dimensional strain system
(B)   two dimensional strain system
(C)   three dimensional strain system
(D)   no strain

18   The relationship between Young’s modulus (E), Bulk modulus (K) and Poisson’s ratio (u) is given by
(A)   E = 3K(1-2u)
(B)   E = 3K(1-u)
(C)   K = 3E(1-u)
(D)   K = 3E(1-2u)

19   The unit of Bulk Modulus is
(A)   MPa
(B)   N
(C)   mm
(D)   unitless

20   When a member is subjected to a constant load over a long period of time, it undergoes a slow permanent deformation. This phenomenon is known as______
(A)   Fatigue
(B)   Creep
(C)   Malleability
(D)   Stiffness

21   A tensile force (P) is acting on a body of length (L) and area of cross section (A). The change in length would be___
(A)   P/AEL
(B)   PL/AE
(C)   PE/AL
(D)   AL/PE

22   The ratio of shear stress to shear strain is called__
(A)   Bulk Modulus
(B)   Modulus of Elasticity
(C)   Poisson’s ratio
(D)   Modulus of Rigidity

23   A steel bar of 40 mm x 40 mm square cross-section is subjected to an axial tensile load of 200 KN. If the length of bar is 2 m and E = 2 x 105 MPa, the elongation of the bar will be____
(A)   1.25 mm
(B)   2.70 mm
(C)   4.05 mm
(D)   5.40 mm

24   Due to which mechanical property, the material can be rolled into thin sheets?
(A)   Ductility
(B)   Malleability
(C)   Brittleness
(D)   Hardness

25   The Force (P) required to punch a hole in the plate having shearing area (A) and shear stress (τ ) is___
(A)   P = τ/A
(B)   P = A/τ
(C)   P = τ x A
(D)   P = τ + A

26   The unit of stiffness is__
(A)   N-m
(B)   m/N
(C)   N
(D)   N/m

27   The slope of the stress-strain curve in the elastic deformation region is___
(A)   Elastic modulus
(B)   Plastic modulus
(C)   Poisson’s ratio
(D)   None of the above

28   The elongation of the bar under certain external load is depend on__
(B)   length of the bar
(C)   material of the bar
(D)   All of the above

Part 02

1   When shear force at a point is zero, then bending moment is ______at that point.
(A)   Zero
(B)   minimum
(C)   maximum
(D)   None of the above

2   Bending moment at a simply supported end is
(A)   Zero
(B)   Maximum
(C)   Minimum
(D)   None of the above

3   A point along the length of a beam subjected to loads where bending moment changes its sign, is known as the point of____
(A)   Inflection
(B)   Maximum stress
(C)   Zero shear force
(D)   Contraflexure

4   A cantilever beam subjected to point load at its free end, then the shape of BMD is
(A)   Triangular
(B)   Rectangular
(C)   Parabolic
(D)   Trapezoidal

5   Maximum bending moment in a cantilever beam with uniformly distributed load (w /unit length) over whole length ‘L’ is
(A)   wL2
(B)   (wL2)/2
(C)   (wL2)/4
(D)   (wL2)/6

6   Maximum bending moment in a simply supported beam of length 1 m with a concentrated load 40N at its mid span is
(A)   40 Nm
(B)   20 Nm
(C)   10 Nm
(D)   5 Nm

7   Which is/are the following assumptions in a theory of simple bending___
(A)   The stress-strain relationship is linear and elastic
(B)   Young’s modulus is the same in tension and compression
(C)   Section which are plane before bending remains plane after bending
(D)   All of the above

8   If ‘σ’ be the bending stress, M = bending moment, I = moment of inertia, R = Radius of curvature and y = distance of the fiber from neutral axis. Then bending equation is,
(A)   σ/y = M/I = E/R
(B)   σ/I = M/y = E/R
(C)   σ/R = M/I = E/y
(D)   None of the above

9   If a circular section having diameter ‘D’ is subjected to a maximum bending moment ‘M’, then maximum bending stress is
(A)   16M/πD3
(B)   32M/πD3
(C)   16M/πD2
(D)   32M/πD2

10   Bending stress at neutral axis is
(A)   Maximum
(B)   Zero
(C)   Cannot be zero
(D)   None of the above

11   The part of the column section in which the load can be applied without causing tensile stress anywhere in the section is called
(A)   Core of section
(B)   Modulus of section
(C)   Area of section
(D)   None of the above

12   Section modulus (Z) of a beam is a function of
(A)   Cross section only
(D)   None of the above

13   For circular section of diameter 100mm, the diameter of Core section is
(A)   50mm
(B)   12.5mm
(C)   25mm
(D)   100mm

14   The core of the rectangular section is of _____shape.
(A)   Triangular
(B)   Rectangular
(C)   Circular
(D)   Rhombus

15   A long shaft of diameter ‘d’ is subjected to torque ‘T’ at its ends. The maximum shear stress is equal to
(A)   16T/πd3
(B)   32T/πd3
(C)   64T/πd3
(D)   8T/πd3

16   The maximum shear stress induced in a power transmitting shaft is
(A)   Directly proportional to torque being transmitted
(B)   Inversely Proportional to the stress induced cube of its diameter
(C)   Both a) and b)
(D)   None of the above

17   The magnitude of stress induced in a shaft due to applied torque varies from
(A)   maximum at the center to zero at the circumference
(B)   zero at the center to maximum at the circumference
(C)   maximum at the center to minimum but not zero at the circumference
(D)   minimum but not zero at the center to maximum at the circumference

18   Two shafts in torsion will have equal strength if
(A)   only diameters of the shafts are same
(B)   only angle of twist of the shafts are same
(C)   only material of the shafts is same
(D)   only torque transmitting capacity of the shafts are same

19   A hollow shaft of same cross-sectional area and material as that of solid shaft transmit
(A)   Same torque
(B)   Lesser torque
(C)   More torque
(D)   cannot be predicted without more data

20   A solid circular shaft of 120 mm diameter is transmitting 100 KW power at 150 rpm. The intensity of maximum induced shear stress in the shaft is___
(A)   32.42 MPa
(B)   18.76 MPa
(C)   25.40 MPa
(D)   14.36 MPa

21   The ratio of average shear stress to the maximum shear stress in a beam with a rectangular cross section is___
(A)   1
(B)   2/3
(C)   3/2
(D)   2

22   What is the nature of distribution of shear stress in a rectangular cross section beam due to shear force?
(A)   Linear
(B)   Parabolic
(C)   Hyperbolic
(D)   Elliptic

23   Which of the following is/are correct about Torsion?
(A)   Torsion is the twisting of an object caused by a moment acting in a plane parallel to the plane of cross section.
(B)   Torsion is the twisting of an object caused by a moment acting in a plane perpendicular to the longitudinal axis of a member.
(C)   Torsion is the twisting of an object caused by a moment acting about the longitudinal axis of a member.
(D)   All of the above

24   The unit of Torque is
(A)   N-m
(B)   MPa
(C)   mm4
(D)   N

25   We can select ______value of diameter from diameter calculated on the basis of shear stress condition and angle of twist condition for overall safety.
(A)   Higher
(B)   Lower
(C)   Average
(D)   None of the above

26   A solid circular shaft is replaced by a hollow circular shaft of same material whose external diameter is twice the internal diameter. Both the shafts are required to transmit the same power at the same speed. If both the shafts are to have the same strength, then % saving in the weight is_____
(A)   94.66
(B)   60
(C)   31.24
(D)   21.69

27   When the body is subjected to eccentric load, then _____types of stresses will be produced in the body.
(A)   only direct stress
(B)   only bending stress
(C)   both direct and bending stresses
(D)   None of the above

28   Which of the following is/are the field examples of eccentric loading?
(A)   Hook
(B)   C-clamp