# 160+ Structural Mechanics Solved MCQs

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1.

## What is elasticity?

A. ability to re-gain It's original size and shape
B. ability to produce permanent deformation
C. both
D. none of above
Answer» A. ability to re-gain It's original size and shape
2.

## What is modular ratio?

A. ratio of deflection in each material
B. ratio of modulus of elasticity of bot h material
C. ratio of load acting in each section
D. all of above
3.

A. 0.0035
B. 0.0005
C. 0.002
D. 0.0175
4.

A. 1 mm
B. 2mm
C. 3mm
D. 4mm
5.

A. Deformation
B. Elongation
C. contraction
D. None of above
6.

## which of the following has same unit?

A. modulus of elasticity, pressure, stress
B. elasticity, strain, stress
C. pressure, strain, stress
D. modulus of elasticity, strain, modulus of rigidity
Answer» A. modulus of elasticity, pressure, stress
7.

## unit of stress is .

A. Pascal
B. Newton
C. N/m2
D. a and c both
Answer» D. a and c both
8.

A. True
B. False
C. none
D. all
9.

## which of the following is type of stress?

A. tensile stress
B. compressive stress
C. shear stress
D. all of the above
Answer» D. all of the above
10.

## Strain is defined as the ratio of

A. change in volume to original volume
B. change in length to original length
C. change in cross-sectional area to original cross-sectional area
D. any one of the above
Answer» B. change in length to original length
11.

## Hooke's law holds good up to

A. yield point
B. limit of proportionality
C. breaking point
D. elastic limit
12.

## Young's modulus is defined as the ratio of

A. volumetric stress and volumetric strain
B. lateral stress and lateral strain
C. longitudinal stress and longitudinal strain
D. shear stress to shear strain
Answer» A. volumetric stress and volumetric strain
13.

A. mm/mm
B. kg/cm
C. kg
D. kg/cm2
14.

## Deformation per unit length in the direction of force is known as

A. Strain
B. lateral strain
C. linear strain
D. linear stress
15.

## It equal and opposite forces applied to a body tend to elongate it, the stress so produced is called

A. internal resistance
B. tensile stress
C. transverse stress
D. compressive stress
16.

## The materials having same elastic properties in all directions are called

A. ideal materials
B. uniform materials
C. isotropic materials
D. elastic materials.
17.

## Modulus of rigidity is defined as the ratio of

A. longitudinal stress and longitudinal strain
B. volumetric stress and volumetric strain
C. lateral stress and lateral strain
D. shear stress and shear strain
Answer» D. shear stress and shear strain
18.

## If the radius of wire stretched by a load is doubled, then its Young's modulus will be

A. Doubled
B. Halved
C. become four times
D. remain unaffected
19.

## The intensity of stress which causes unit strain is called

A. unit stress
B. bulk modulus
C. modulus of rigidity
D. modulus of elasticity
20.

## Which of the following has no unit

A. kinematic viscosity
B. surface tension
C. bulk modulus
D. strain
21.

A. P=π2EIL2
B. P=πL2EI
C. P=πEIL2
D. P=π2EIL3
22.

## Rankine-Golden formula accounts for direct as well as buckling stress and is applicable to

A. very long columns
B. long columns
C. short columns
D. intermediate columns
23.

A. ML2/3EI
B. ML2/4EI
C. ML2/6EI
D. ML2/2EI
24.

## The ratio of the effective length of a column and minimum radius of gyration of its cross-sectional area, is known

A. buckling factor
B. slenderness ratio
C. crippling factor
D. none of these
25.

A. a column
B. a strut
C. a tie
D. a stanchion
26.

## Columns of given length, cross-section and material have different values of buckling loads for different end conditions. The strongest column is one whose

A. one end is fixed and other end is hinged
B. both ends are hinged or pin jointed
C. one end is fixed and the other end entirely free
D. both the ends are fixed
Answer» D. both the ends are fixed
27.

A. 117.2
B. 17.3
C. 173.2
D. 137.2
28.

A. 0.5L
B. 0.7L
C. L
D. 2L
29.

## The radius of gyration of a squar section is not proportional to

A. square root of the moment of inertia
B. square root of the inverse of the area
C. square root of the moment of inertia divided by area of the section
D. side of squar
30.

A. 1.288 kN
B. 12.88 kN
C. 128.8 kN
D. 288.0 kN
31.

## A sudden increase or decrease in shear force diagram between any two points indicates that there is

B. Point loads between the two points
C. U.D.L. between the two points
D. None of these
32.

## A beam is a structural member which is subjected to

A. Axial tension or compression
C. Twisting moment
D. No load, but its axis should be horizontal and x-section rectangular or circular
33.

## Which of the following are statically determinate beams?

A. Only simply supported beams
B. Cantilever, overhanging and simply supported
C. Fixed beams
D. Continuous beams
Answer» B. Cantilever, overhanging and simply supported
34.

## A cantilever is a beam whose

A. Both ends are supported either on rollers or hinges
B. One end is fixed and other end is free
C. Both ends are fixed
D. Whose both or one of the end has overhang
Answer» B. One end is fixed and other end is free
35.

## In a cantilever carrying a uniformly varying load starting from zero at the free end, the shear force diagram is

A. A horizontal line parallel to x-axis
B. A line inclined to x-axis
C. Follows a parabolic law
D. Follows a cubic law
Answer» C. Follows a parabolic law
36.

## In a cantilever carrying a uniformly varying load starting from zero at the free end, the Bending moment diagram is

A. A horizontal line parallel to x-axis
B. A line inclined to x-axis
C. Follows a parabolic law
D. Follows a cubic law
Answer» D. Follows a cubic law
37.

## In a simply supported beam, bending moment at the end

A. Is always zero if it does not carry couple at the end
B. Is zero, if the beam has uniformly distributed load only
C. Is zero if the beam has concentrated loads only
D. May or may not be zero
Answer» A. Is always zero if it does not carry couple at the end
38.

## For any part of the beam, between two concentrated load Shear force diagram is a

A. Horizontal straight line
B. Vertical straight line
C. Line inclined to x-axis
D. Parabola
39.

## For any part of a beam between two concentrated load, Bending moment diagram is a

A. Horizontal straight line
B. Vertical straight line
C. Line inclined to x-axis
D. Parabola
Answer» C. Line inclined to x-axis
40.

## For any part of a beam subjected to uniformly distributed load, Shear force diagram is

A. Horizontal straight line
B. Vertical straight line
C. Line inclined to x-axis
D. Parabola
Answer» C. Line inclined to x-axis
41.

## For any part of a beam subjected to uniformly distributed load, bending moment diagram is

A. Horizontal straight line
B. Vertical straight line
C. Line inclined to x-axis
D. Parabola
42.

## In a simple supported beam having length = l and subjected to a concentrated load (W) at mid-point.

A. Maximum Bending moment = Wl/4 at the mid-point
B. Maximum Bending moment = Wl/4 at the end
C. Maximum Bending moment = Wl/8 at the mid-point
D. Maximum Bending moment = Wl/8 at the end
Answer» A. Maximum Bending moment = Wl/4 at the mid-point
43.

## In a cantilever subjected to a concentrated load (W) at the free end and having length =l, Maximum bending moment is

A. Wl at the free end
B. Wl at the fixed end
C. Wl/2 at the fixed end
D. Wl at the free end
Answer» B. Wl at the fixed end
44.

## At a point in a simply supported or overhanging beam where Shear force changes sign and = 0, Bending moment is

A. Maximum
B. Zero
C. Either increasing or decreasing
D. Infinity
45.

## In a cantilever subjected to a combination of concentrated load, uniformly distributed load and uniformly varying load, Maximum bending moment is

A. Where shear force=0
B. At the free end
C. At the fixed end
D. At the mid-point
Answer» C. At the fixed end
46.

## Point of contra-flexure is a

A. Point where Shear force is maximum
B. Point where Bending moment is maximum
C. Point where Bending moment is zero
D. Point where Bending moment=0 but also changes sign from positive to negative
Answer» D. Point where Bending moment=0 but also changes sign from positive to negative
47.

## Point of contra-flexure is also called

A. Point of maximum Shear force
B. Point of maximum Bending moment
C. Point of inflexion
D. Fixed end
48.

## The slope of shear force line at any section of the beam is also called

A. Bending moment at that section
C. Maximum Shear force
D. Maximum bending moment
49.

## The direction of shear stress in a loaded beam is

A. Horizontal
B. Horizontal as well as vertical
C. Vertical
D. None
Answer» B. Horizontal as well as vertical
50.

## Shear stress in the beam acting on the cross section is

A. Normal to the cross section
B. Tangential to the cross section
C. Neither normal nor tangential
D. None
Answer» B. Tangential to the cross section
51.

52.

## Which law is also called as the elasticity law?

A. Bernoulli’s law
B. Stress law
C. Hooke’s law
D. Poisson’s law
53.

A. Isotropic
B. Brittle
C. Homogeneous
D. Hard
54.

## The calculation of the moment of the body due to the loadings involve a quantity called ____________

A. Moment
B. Inertia
C. Moment of Inertia
D. Rotation
55.

A. True
B. False
C. none
D. all
56.

## What is parallel axis theorem and to whom it is applied?

A. Theorem used to add the two mutually perpendicular moment of inertias for areas
B. Theorem used to add the two mutually perpendicular moment of inertias for volumes
C. Theorem used to add the two mutually perpendicular moment of inertias
D. Theorem used to add the two mutually perpendicular moment of inertias for vectors
Answer» A. Theorem used to add the two mutually perpendicular moment of inertias for areas
57.

A. Linear
B. Non-Linear
C. Perpendicular
D. Parallel
58.

A. Linearly
B. Non-Linearly
C. Parabolically
D. Cubically
59.

A. 2WL/E
B. WL/E
C. WL/2E
D. WL/3E
60.

A. 1 mm
B. 0.5 mm
C. 0.75 mm
D. 1.5 mm
61.

A. 160 GPa
B. 208 GPa
C. 120 GPa
D. 104 GPa
62.

## If the value of poisson‟s ratio is zero

A. the lateral strain is high
B. the material is perfectly elastic
C. there is no linear strain in the material
D. none of the above
Answer» C. there is no linear strain in the material
63.

## The ratio between direct stress and volumetric strain is:

A. Bulk modulus
B. Poisson’s ratio
C. Factor of safety
D. Modulus of rigidity
64.

A. 20kN/mm2
B. 0.02kN/mm2
C. 200 kN/mm2
D. 2000kN/mm2
65.

A. 0.25
B. 0.33
C. 0.50
D. 0.75
66.

## Consider a 250mmx15mmx10mm steel bar which is free to expand is heated from 150C to 400C. what will be developed?

A. Compressive stress
B. Tensile stress
C. Shear stress
D. No stress
67.

A. 25 cm
B. 26.19cm
C. 30.14 cm
D. 27.9 cm
68.

A. more than 50%
B. 25—50%
C. 10—25%
D. negligible.
69.

## In a tensile test, near the elastic limit zone, the

A. tensile strain increases more quickly
B. tensile strain decreases more quickly
C. tensile strain increases in proportion to the stress
D. tensile strain decreases in proportion to the stress
Answer» A. tensile strain increases more quickly
70.

## The stress necessary to initiate yielding is

A. considerably greater than that necessary to continue it
B. considerably lesser than that necessary to continue it
C. greater than that necessary to stop it
D. lesser than that necessary to stop it
Answer» A. considerably greater than that necessary to continue it
71.

## Rupture stress is

A. breaking stress
D. load at breaking point/neck area
72.

## stress at which extension of material takes place more quickly as compared to increase in load is called

A. elastic point of the material
B. plastic point of the material
C. breaking point of the material
D. yielding point of the material
Answer» D. yielding point of the material
73.

## The energy absorbed in a body, when it is strained within the elastic limits, is known as

A. strain energy
B. resilience
C. proof resilience
D. modulus of resilience
74.

## Resilience of a material is considered when it is subjected to

A. frequent heat treatment
B. fatigue
C. creep
75.

## The maximum strain energy that can be stored in a body is known as

A. impact energy
B. resilience
C. proof resilience
D. modulus of resilience
76.

## The total strain energy stored in a body is termed as

A. resilience
B. proof resilience
C. modulus of resilience
D. toughness
77.

## Proof resilience per material is known as

A. resilience
B. proof resilience
C. modulus of resilience
D. toughness
78.

A. same
B. half
C. two times
D. four times
79.

A. same
B. twice
C. four times
D. eight times
80.

A. 4 tonnes/cm2
B. 8 tonnes/cm2
C. 16 tonnes/cm2
D. 22 tonnes/cm2
81.

## Tensile strength of a material is obtained by dividing the maximum load during the test by the

A. area at the time of fracture
B. original cross-sectional area
C. average of (a) and (b)
D. minimum area after fracture
82.

A. 10,000 N.mm
B. 20,000 N.mm
C. 25,000 N.mm
D. 50,000 N.mm
83.

A. 14 cm2
B. 15 cm2
C. 16 cm2
D. 17 cm2
84.

A. 72 N/mm2
B. 144 N/mm2
C. 120 N/mm2
D. 240 N/mm2
85.

A. 10 mm
B. 20 mm
C. 7 mm
D. 35 mm
86.

A. 0.2
B. 0.25
C. 0.3
D. 0.35
87.

A. 150 KN
B. 200 KN
C. 400 KN
D. 500 KN
88.

A. 6
B. 9
C. 8
D. 2
89.

A. 1
B. 1/12
C. 1/3
D. 1/4
90.

## The axis about which moment of area is taken is known as .

A. Axis of area
B. Axis of moment
C. Axis of reference
D. Axis of rotation
91.

## What is the formula of theorem of parallel axis?

A. Iab = Ig + ah
B. Iab = ah2 + Ig
C. Iab = Ig – ah2
D. Izz = Iyy + Ixx
Answer» B. Iab = ah2 + Ig
92.

A. π/64
B. π/4
C. π/16
D. π/2
93.

A. mm
B. mm2
C. mm3
D. mm4
94.

## What is the formula of theorem of perpendicular axis?

A. Izz = Ixx – Iyy
B. Izz = Ixx + Ah2
C. Izz – Ixx = Iyy
D. None of the above
Answer» C. Izz – Ixx = Iyy
95.

A. mm
B. mm2
C. mm3
D. mm4
96.

A. mm
B. mm2
C. mm3
D. mm4
97.

A. k2 = I/A
B. k2 = I2/A
C. k2 = I2/A2
D. k2 = (I/A)1/2
98.

A. 1.5cm
B. 2.0cm
C. 2.5cm
D. 3.0cm
99.

## Moment of inertia of any section about an axis passing through its C.G is

A. Maximum
B. Minimum
C. Depends upon the dimensions of the section
D. Depends upon the shape of the section
100.

A. 9
B. 4
C. 2
D. 3