Important MCQ on Strength of Materials
1) One kg force is equal to
(a) 7.8 N
(b) 8.9 N
(c) 9.8 N✔
(d) 12 N
2) Concurrent forces are those forces whose lines of action
(a) lie on the same line
(b) meet at one point✔
(c) meet on the same plane
(d) none of these
3) A couple produces
(a) translatory motion
(b) rotational motion✔
(c) combined translatory and rotational motion
(d) none of the above
4) The centre of gravity of an equilateral trangle with each side a, is
(a) √3 a/2
(b) 2√3 a
(c) a/(2√3)✔
(d) 3√2 a
5) The centre of gravity of a semi-circle lies at a istance of
(a) 3r/8
(b) 4r/3Π ✔
(c) 8r/3
(d) 3r/4Π
6) The centre of gravity of a right crcular solid cone is at a distance of
(a) h / 2
(b) h / 3
(c) h / 4✔
(d) h / 6
7) The centr of gravity of a quadrant of a circle lies along its central radius (r) at a distance of
(a) 0.5 r
(b) 0.6 r✔
(c) 0.7 r
(d) 0.8 r
8) The centre of gravity a T-section 100 mm x 150 mm x 50 mm from its bottom is
(a) 50 mm
(b) 75 mm
(c) 87.5 mm✔
(d) 125 mm
9) Moment of inertia is the
(a) second moment of force
(b) second moment of area
(c) second moment of mass
(d) all of these✔
10) The unit of moment of inertia of an area is
(a) kg-m2
(b) kg-m-s2
(c) kg/m2
(d) m4✔
11) Mass moment of inertia of a thin rod about its one end is
(a) same as
(b) twice
(c) thrice
(d) four times✔
12) The moment of inertia of a square of side (a) about an axis through its centre of gravity is
(a) a4/4
(b) a4/8
(c) a4/12✔
(d) a4/36
13) The moment of inertia of a rectangular section 3cm wide and 4cm deep about X-X axis is
(a) 9 cm4
(b) 9 cm4
(c) 16 cm4✔
(d) 0 cm4
14) The moment of inertia of a square of side about its diagonal is
(a) a2 / 8
(b) a3 / 12
(c) a4 / 12✔
(d) a4 / 16
15) Moment of inertia of a circular section about its diameter (d) is
(a) Πd3 / 16
(b) Πd3 / 32
(c) Πd4 / 32
(d) Πd4 / 64✔
16) Moment of inertia of a circular section about an axis perpendicular to the section is
(a) Πd3 / 16
(b) Πd3 / 32
(c) Πd4 / 32✔
(d) Πd4 / 64
17) Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its (c)G. and parallel to the base, is
(a) bh3 / 4
(b) bh3 / 8
(c) bh3 / 12
(d) bh3 / 36✔
18) Moment of inertia of a triangular section of base (b) and height (h) about an axis through its base, is
(a) bh3 / 4
(b) bh3 / 8
(c) bh3 / 12✔
(d) bh3 / 36
19) The static friction
(a) bears a constant ratio to the normal reaction between the two surfaces
(b) is independent of the area of contact, between the two surfaces
(c) always acts in a direction, opposite to that in which the body tends to move
(d) all of the above✔
20) The minimum force required to slide a body of weight W on a rough horizontal plane is
(a) W sinθ
(b) W cosθ
(c) W tanθ ✔
(d) none of these
21) Coefficient of friction depends upon
(a) area of contact only
(b) nature of surface only✔
(c) both (a) and (b)
(d) none of these
22) The unit of work in S.I. units is
(a) newton
(b) erg
(c) kg-m
(d) joule✔
23) One joule is equal to
(a) 0.1 N - m
(b) 1 N - m✔
(c) 10 N - m
(d) 100 N - m
24) Joule is the unit of
(a) force
(b) work✔
(c) power
(d) energy
25) The unit of power in S.I. units is
(a) horsepower
(b) joule
(c) watt✔
(d) kg-m
26) One watt is equal to
(a) 0.1 joule / s
(b) 1 joule / s✔
(c) 10 joules / s
(d) 100 joules / s
27) The unit of energy in S.I. units is
(a) dyne
(b) watt
(c) kg – m
(d) joule✔
28) The modulus of elasticity for mild steel is approximately equal to
(a) 10 kN/mm2
(b) 80 kN/mm2
(c) 100 kN/mm2
(d) 210 kN/mm2✔
29) The unit of force in S.I. system of units of
(a) dyne
(b) kilogram
(c) newton✔
(d) watt
30) Young's modulus may be defined as the ratio of
(a) linear stress to lateral strain
(b) lateral strain to linear strain
(c) linear stress to linear strain✔
(d) shear stress to shear strain
31) Modulus of rigidity may be defined as the ratio of
(a) linear stress to lateral strain
(b) lateral strain to linear strain
(c) linear stress to linear strain
(d) shear stress to shear strain✔
32) The deformation of a bar under its own weight is
(a) equal to
(b) half✔
(c) double
(d) quadruple
33) The elongation of a conical bar under its own weight is
(a) equal to
(b) half
(c) one-third✔
(d) two-third
36) Strain rosetters are used tc
(a) measure shear strain
(b) measure linear strain✔
(c) measure volumetric strain
(d) relieve strain
37) Modular ratio of the two materials is the ratio of
(a) linear stress to linear strain
(b) shear stress to shear strain
(c) their modulus of elasticities✔
(d) their modulus of rigidities
38) The Poisson's ratio for steel 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
39) 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
40) The ratio of change in volume to the original volume is called
(a) linear strain
(b) lateral strain
(c) volumetric strain✔
(d) Poisson's ratio
41) The ratio of bulk modulus to Young's modulus for a Poisson's ratio of 0.25 will be
(a) 1/3
(b) 2/3✔
(c) 1
(d) 3/2
41-a) Within elastic limit, shear stress is
(a) equal to
(b) less than
(c) directly proportional to✔
(d) inversely proportional to
42) Shear modulus is the ratio of
(a) linear stress to linear strain
(b) linear stress to lateral strain
(c) volumetric strain to linear strain
(d) shear stress to shear strain✔
42) Principle plane is a plane on which the shear stress is
(a) zero✔
(b) minimum
(c) maximum
43) A body is subjected to two normal stresses 20 kN / m2 (tensile) and 10 kN / m2 (compressive) acting perpendicular to each other. The maximum shear stress is
(a) 5 kN / m2
(b) 10 kN / m2
(c) 15 kN / m2✔
(d) 20 kN / m2
44) The maximum shear stress is
(a) equal to
(b) one-fourth
(c) one-half✔
(d) twice
45) A beam extending beyond the supports is called
(a) simply supported beam
(b) fixed beam
(c) overhanging beam✔
(d) cantilever beam
45-a) A beam encastered at both the ends is called
(a) simply supported beam
(b) fixed beam✔
(c) cantilever beam
(d) continuous beam
46) A beam supported on more than two supports is called
(a) simply supported beam
(b) fixed beam
(c) overhanging beam
(d) continuous beam✔
46-a) A cantilever beam is one which is
(a) fixed at both ends
(b) fixed at one end and free at the other end✔
(c) supported at its ends
(d) supported on more than two supports
47) A continuous beam is one which is
(a) fixed at both ends
(b) fixed at one end and free at the other end
(c) supported on more than two supports✔
(d) extending beyond the supports
48) The bending moment on a section is maximum where shear force is
(a) minimum
(b) maximum
(c) changing sign✔
(d) zero
49) When a load on the free end of a cantilever beam is increased, failure will occur
(a) at the free end
(b) at the fixed end✔
(c) in the middle of the beam
(d) at a distance 21 / 3 from free end
50) When a cantilever beam is loaded with concentrated loads, the bending moment diagram will be a
(a) horizontal straight line
(b) vertical straight line
(c) inclined straight line✔
(d) parabolic curve
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| Important MCQ on Strength of Materials |
51) The shear force of a cantilever beam of length l carrying a uniformly distributed load of w per unit length is
(a) zero✔
(b) wl /4
(c) wl / 2
(d) wl
52) The shear force of a cantilever beam of length / carrying a uniformly distributed load of w per unit length is
(a) zero
(b) wl / 4
(c) wl / 2
(d) wl✔
53) The shear force diagram of a cantilever beam of length l and carrying a uniformly distributed load of w per unit length will be
(a) a right angled triangle✔
(b) an issoscles triabgle
(c) an equilateral triangle
(d) a rectangle
54) The bending moment of a cantilever beam of length l and carrying a uniformly distributed load of w per unit length is
(a) zero✔
(b) wl / 4
(c) wl / 2
(d) wl
55) The shear force and bending moment zre zero at the free end of a cantilever beam, if it carries a
(a) point load at the free end
(b) point load at the middle of its length
(c) uniformly distributed load over the whole length✔
(d) none of the above
56) The bending moment of a cantilever beam of length l and carrying a uniformly distributed load of w per unit length is
(a) wl / 4
(b) wl / 2
(c) wl
(d) wl2 / 2✔
57) The shear force in the centre of a simply supported beam carrying a uniformly distributed load of w per unit length, is
(a) zero✔
(b) wl2 / 2
(c) wl2 / 4
(d) wl2 / 8
58) The bending moment in the centre of a simply supported beam carrying a uniformly distributed load of w per unit length is
(a) zero
(b) wl2 / 2
(c) wl2 / 4
(d) wl2 / 8✔
59) The shear force at the ends of a simply supported beam carrying a uniformly distributed load of w per unit length is
(a) zero at its both ends
(b) wl at one end and - wl at the other end
(c) wl/2 at one end and - wl/2 at the other end✔
(d) wl2/2 at one end and - wl2/2 at the other end
60) The shear force diagram for a simply supported beam carrying a uniformly distributed load of w per unit length, consists of
(a) one right angled triangle
(b) two right angled triangles✔
(c) one equilateral triangle
(d) two equilateral triangles
61) The bending moment diagram for a simply supported beam carrying a uniformly distributed load of w per unit length, will be
(a) a horizontal line
(b) a vertical line
(c) an inclined line
(d) a parabolic curve✔
62) The shear force at the centre of a simply supported beam with a gradually varying load from zero at both ends to w per metre at the centre, is
(a) zero✔
(b) wl / 4
(c) wl / 2
(d) wl2 / 2
63) The point of contraflexure is a point where
(a) shear force changes sign
(b) bending moment changes sign✔
(c) shear force is maximum
(d) bending moment is maximum
64) When shear force at a point is zero, then bending moment is
(a) zero
(b) minimum
(c) maximum✔
(d) infinity
65) In a simply supported beam carrying a uniformly distributed load w per unit length, the po nt of contraflexure
(a) lies in the centre of the beam
(b) ies at the ends of the beam
(c) depends upon the length of beam
(d) does not exist✔
66) When there is a sudden increase or decrease in shear force diagram between any two points, it indicates that there is a
(a) point load at the two points✔
(b) no loading between the two points
(c) uniformly distributed load between the two points
(d) uniformly varying load between the two points
67) When the shear force diagram is a parabolic curve between two points, it indicates that there is a
(a) point load at the two points
(b) no loading between the two points
(c) uniformly distributed load between the two points
(d) uniformly varying load between the two points✔
68) Which of the following statement is correct?
(a) A continuous beam has only two supports at the ends
(b) A uniformly distributed load spreads uniformly over the whole length of a beam. ✔
(c) The bending moment is maximum where whear force is maximum.
(d) The maximum bending moment of a simply supported beam of length l with a central point load W is W l/8.
69) In a beam where shear force changes sign, the bending moment will be
(a) zero
(b) minimum
(c) maximum✔
(d) infinity
70) The point of contraflexure occurs in
(a) cantilever beams
(b) simply supported beams
(c) overhanging beams✔
(d) fixed beams
71) In a simple bending of beams, the stress in the beam varies
(a) linearly✔
(b) parabolically
(c) hyperbolically
(d) elliptically
72) When a beam is subjected to a bending moment, the strain in a layer is
(a) equal to
(b) directly proportional to✔
(c) inversely proportional to
(d) independent of
73) A section of beam is said to be in pure bending, if it is subjected to
(a) constant bending moment and constant shear force
(b) constant shear force and zero bending moment
(c) constant bending moment and zero shear force✔
(d) none of the above
74) When a beam is subjected to bending moment, the stress at any point is
(a) equal to
(b) directly proportional to✔
(c) inversely proportional to
(d) independent of
75) The neutral axis of the cross-section a beam is that axis at which the bending stress is
(a) zero✔
(b) minimum
(c) maximum
(d) infinity
76) The section nodulus (Z) of a beam is given by
(a) I / y✔
(b) I.y
(c) y / I
(d) M / I
77) The section modulus of a rectangular section about an axis through its (c)G., is
(a) b / 2
(b) d / 2
(c) bd2/2
(d) bd2/6✔
78) The section modulus of a circular section about an axis through its (c)G., is
(a) Πd2/ 4
(b) Πd2/ 16
(c) Πd3/ 16
(d) Πd3/ 32✔
79) When a cantilever beam is loaded at its free end, the maximum compressive stress shall develop at
(a) bottom fibre✔
(b) top fibre
(c) neutral axis
(d) centre of gravity
80) A beam of uniform strength may be obtained by
(a) keeping the width uniform and varying the depth
(b) keeping the depth uniform and varying the width
(c) varying the width and depth both
(d) any one of the above✔
81) 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
82) The bending stress in a beam is______bending moment.
(a) equal to
(b) less than
(c) more than
(d) directly proportional to✔
84) At the neutral axis of a beam
(a) the layers are subjected to maximum bending stress
(b) the layers are subjected to minimum bending stress
(c) the layers are subjected to compression
(d) the layers do not undergo any strain✔
85) The neutral axis of a beam is subjected to
(a) zero✔
(b) maximum tensile
(c) minimum tensile
(d) maximum compressive
86) In a beam subjected to pure bending, the intensity of stress in any fibre is
(a) equal to
(b) less than
(c) more than
(d) directly proportional to✔
87) When a rectangular beam is loaded transversely, the maximum tensile stress is developed on the
(a) top layer✔
(b) bottom layer
(c) neutral axis
(d) every cross-section
88) At the neutral axis of a beam, the shear stress is
(a) zero
(b) minimum
(c) maximum✔
(d) infinity
89) The maximum shear stress developed in a beam of rectangular section is
(a) equal to
(b) 4 / 3 time
(c) 1.5 times✔
(d) twice
90) A beam of triangular section is placed with its base horizontal. The maximum shear stress occurs at
(a) apex of the triangle
(b) mid of the height✔
(c) centre of gravity of the triangle
(d) base of the triangle
91) A beam of T-section is subjected to a shear force of F. The maximum shear force will occur at the
(a) top of the section
(b) bottom of the section
(c) neutral axis of the section✔
(d) junction of web and flange
92) A rectangular beam of length l supported at its two ends carries a central point load W. The maximum deflection occurs
(a) at the ends
(b) at l / 3 from both ends✔
(c) at the centre
(d) none of these
93) The maximum deflection of a fixed beam carrying a central point load lies at
(a) fixed ends
(b) centre of beam✔
(c) l / 3 from fixed ends
(d) none of these
94) The product of Young's modulus (E) and moment of inertia (I) is known as
(a) modulus of rigidity
(b) bulk modulus
(c) flexural rigidity✔
(d) torsional rigidity
95) When a shaft is subjected to a twisting moment, every cross-section of the shaft will be under
(a) tensile stress
(b) compressive stress
(c) shear stress✔
(d) bending stress
96) The shear stress at the centre of a circular shaft under torsion is
(a) zero✔
(b) minimum
(c) maximum
(d) infinity
97) The shear stress at the outermost fibres of a circular shaft under torsion is
(a) zero
(b) minimum
(c) maximum✔
(d) infinity
98) In spring balances, the spring is used
(a) to apply forces
(b) to measure forces✔
(c) to absorb shocks
(d) to store strain energy
99) A spring used to absorb shocks and vibrations is
(a) conical spring
(b) torsion spring
(c) leaf spring✔
(d) disc spring
100) The load required to produce a unit deflection in a spring is called
(a) flexural rigidity
(b) torsional rigidity
(c) spring stiffness✔
(d) Young's modulus
101) A leaf spring is supported at the
(a) ends and loaded at the centre
(b) centre and loaded at the ends✔
(c) ends and loaded anywhere
(d) centre and loaded anywhere
102) For a 25 mm hole drilled in plates, the diameter of rivet shank should be
(a) 23 mm✔
(b) 24.5 mm
(c) 25 mm
(d) 26 mm
103) A lap joint is always in
(a) single✔
(b) double
104) If the tearing efficiency of a riveted joint is 50%, then ratio of rivet hole diameter to the pitch of rivets is
(a) 0.2
(b) 0.3
(c) 0.5✔
(d) 0.6
105) Transverse fillet welds are designed for
(a) tensile strength✔
(b) compressive strength
(c) shear strength
(d) bending strength
105-a) Lame's theory is associated with
(a) thin cylindrical shells
(b) thick cylindrical shells✔
(c) direct and bending stresses
(d) none of these
106) The limit of eccentricity for no tensile condition for a column of circular section of diameter
(a) d / 4
(b) d / 8✔
(c) d / 12
(d) d / 16
107) Compression members always tend to buckle in the direction of the
(a) axis of load
(b) perpendicular to the axis of load
(c) minimum cross section
(d) least radius of gyration✔
108) The direct stress induced in a long column is
(a) same
(b) more
(c) less
(d) negligible✔
109) A column that fails due to direct strss, is called
(a) short column✔
(b) long column
(c) weak column
(d) medium column
110) According to Euler's column theory, the crippling load for a column of length (l) fixed at both ends is
(a) equal to
(b) two times
(c) four times✔
(d) eight times
111) In the Euler's formula, the value of C for a column with one end fixed and the other end free, is
(a) 1/2✔
(b) 1
(c) 2
(d) 4
112) A column of length (l) with both ends fixed may be consdered as equivalent to a column of length
(a) l / 8
(b) l / 4
(c) l / 2
(d) l✔
113) A colum of length (l) with both ends fixed may be considered as equivalent to a column of length
(a) l / 8
(b) l / 4✔
(c) l / 2
(d) l
115) The columns whose slenderness ratio is less than 80, are known as
(a) short column✔
(b) long column
(c) weak column
(d) medium column
116) A column with maximum equivalent length has
(a) both ends hinged
(b) both ends fixed
(c) one end fixed and the other end hinged
(d) one end fixed and the other end free✔
117) Euler's formula holds good only for
(a) short column
(b) long column✔
(c) both short and long columns
(d) weak columns
118) A column is said to be a short column, when
(a) its length is very small
(b) its cross-sectional area is small
(c) the ratio of its length to the least radius of gyration is less than 80. ✔
(d) the ratio of its length to the least radius of gyration is more than 80.
120) The Rankine's constant for a mild steel column with both ends hinged is
(a) 1 / 750
(b) 1 / 1600
(c) 1 / 7500✔
(d) 1 / 9000
121) The Rankine's formula holds good for
(a) short column
(b) long columns
(c) both short and long columns✔
(d) weak columns
122) In case of eccentrically loaded struts
(a) solid section
(b) hollow section
(c) composite section✔
(d) reinforced section
123) A masonry dam may fail du to
(a) tension in the masonry of the dam and its base
(b) overturning of the dam
(c) crushing of masonry at the base of the dam
(d) any one of the above✔
124) A reinforced cement concrete beam is considered to be made of
(a) homogeneous material
(b) hetrogeneous material✔
(c) composite material
(d) isotropic material
125) The steel bars in a reinforced cement concrete beam are embedded
(a) in the centre
(b) near the bottom✔
(c) near the top
(d) at any position
126) The tensile test is carried on
(a) ductile✔
(b) brittle
(c) malleable
(d) plastic
127) The compression test is carried on
(a) ductile
(b) brittle✔
(c) malleable
(d) plastic
128) The compressive strength of brittle materials is
(a) equal to
(b) less than
(c) greater than✔
129) A tensile test is performed on a mild steel round bar. Its diameter after fracture will
(a) remain same
(b) increase
(c) decrease✔
(d) depend upon rate of loading
130) Factor of safety is defined as the ratio of
(a) ultimate stress to working stress✔
(b) working stress to ultimate stress
(c) breaking stress to ultimate stress
(d) ultimate stress to breakingstress
