Latest Strength Of Materials Objective Questions For Freshers
1.The effective length of a fillet weld designed to transmit axial load shall not be less than
2 x size of weld
4 x size of weld
6 x size of weld
10 x size of weld
ANSWER : : 4 x size of weld
2.Effective length of a weld is equal to
overall length – weld size
overall length – throat thickness
overall length – 2 x weld size
overall length – 2 x throat thickness
ANSWER : : overall length – 2 x weld size
3.For an isotropic, homogeneous and elastic material obeying Hooke’s law, number of independent elastic constants is
2
3
9
1
ANSWER : : 2
4.Weakest section in a fillet weld is
throat of the fillet
smaller side
side parallel to force
side perpendicular to force
ANSWER : : throat of the fillet
5.In a thin cylindrical shell, the ratio of longitudinal stress to hoop stress is
0.5
1
2
4
ANSWER : : 2
6.Limit of proportionality depends upon
area of cross-section
type of loading
type of material
all of the above
ANSWER : : type of material
7.If the Young’s modulus of elasticity of a material is twice its modulus of rigidity, then the Poisson’s ratio of the material is
-1
-0.5
0.5
zero
ANSWER : : zero
8.According to Unwin’s formula, the dia�meter of rivet in mm to suit the t mm thickness of plate is given by
6t
6Vt
1.9-y/t
1.5 t+ 4
ANSWER : : 6Vt
9.The elongation of a conical bar under its own weight is equal to
that of a prismatic bar of same length
one half that of a prismatic bar of same length
one third that of a prismatic bar of same length
one fourth that of a prismatic bar of same length
ANSWER : : one third that of a prismatic bar of same length
10.If a material has identical properties in all directions, it is said to be
homogeneous
isotropic
elastic
orthotropic
ANSWER : : isotropic
11.Two bars of different materials are of the same size and are subjected to same tensile forces. If the bars have unit elongations in the ratio of 4 : 7, then the ratio of moduli of elasticity of the two materials is
7:4
4:7
4:17
16 :49
ANSWER : : 7:4
12.If a point in a strained material is subjected to equal normal and tangential stresses, then the angle of obliquity is
0�
45�
tan”1 (1/2)
tan”1 (2)
ANSWER : : 45�
13.Limiting values of Poisson’s ratio are
– 1 and 0.5
-land-0.5
1 and – 0.5
0 and 0.5
ANSWER : : – 1 and 0.5
14.A prismatic bar of volume V is subjected to a tensile force in longitudinal direction. If Poisson’s ratio of the material is u and longitudinal strain is e, then the final volume of the bar becomes
(l + e)(l-u)2V
(l-e)2(l + ue)V
(l + e)(l-ne)2V
(l-ue)3V
ANSWER : : (l + e)(l-ne)2V
15.At a point in a strained body carrying two unequal unlike principal stresses pi and p2 (Pi > P2X the maximum shear stress is given by
p,/2
p2/2
(p,-p2)/2
(p, + p2)/2
ANSWER : : (p, + p2)/2
16.If a composite bar of steel and copper is heated, then the copper bar will be under
tension
compression
shear
torsion
ANSWER : : compression
17.The relationship between Young’s, modulus of elasticity E, bulk modulus K and Poisson’s ratio u is given by
E = 2K(l-2u.)
E = 3K(l + u)
E = 3K(l-2u)
E = 2K(l + u)
ANSWER : : E = 3K(l-2u)
18.Effective throat thickness of a fillet weld is
0.707 x size of weld
1.414 x size of weld
a function of the angle between fusion faces
equal to the side of the fillet
ANSWER : : a function of the angle between fusion faces
19.Size of fillet weld with unequal legs is equal to
smaller leg length
longer leg length
throat thickness
average of smaller and longer leg lengths
ANSWER : : smaller leg length
20.If all the dimensions of a prismatic bar are doubled, then the maximum stress produced in it under its own weight will
decrease
remain unchanged
increase to two times
increase to four times
ANSWER : : increase to two times
21.Size of a right angled fillet weld is given by
0.707 x throat thickness
0.414 x throat thickness
2.0 x throat thickness
throat thickness
ANSWER : : 0.414 x throat thickness
22.A flat carrying a pull of 69C kN is con-nected to a gusset plate using rivets. If the pulls required to shear the rivet, to crush the rivet and to tear the plate per pitch length are 68.5 kN, 46 kN and 69 kN respectively, then the number of rivets required is
10
12
15
20
ANSWER : : 15
23.If the rivet value is 16.8 kN and force in the member is 16.3 kN, then the number of rivets required for the connection of the member to a gusset plate is
1
2
3
4
ANSWER : : 2
24.If a prismatic member with area of cross-section A is subjected to a tensile load P, then the maximum shear stress and its inclination with the direction of load respectively are
P/A and 45�
P/2Aand45�
P/2A and 60�
P/A and 30�
ANSWER : : P/2Aand45�
25.Rate of change of bending moment is equal to
shear force
deflection
slope
rate of loading
ANSWER : : rate of loading
26.A flitched beam consists of a wooden joist 150 mm wide and 300 mm deep strengthened by steel plates 10 mm thick and 300 mm deep one on either side of the joist. If modulus of elasticity of steel is 20 times that of wood, then the width of equivalent wooden section will be
150 mm
350 mm
500 mm
550 mm
ANSWER : : 550 mm
27.The maximum bending moment due to a moving load on a fixed ended beam occurs
at a support
always at the midspan
under the load only
none of the above
ANSWER : : at a support
28.Maximum bending moment in a beam occurs where
deflection is zero
shear force is maximum
shear force is minimum
shear force changes sign
ANSWER : : shear force changes sign
29.A beam of square cross-section with side 100 mm is placed with one diagonal vertical. If the shear force acting on the section is 10 kN, the maximum shear stress is
1 N/mm2
1.125 N/mm2
2 N/mm2
2.25 N/mm2
ANSWER : : 1.125 N/mm2
30.Of the several prismatic beams of equal lengths, the strongest in flexure is the one having maximum
moment of inertia
section modulus
tensile strength
area of cross-section
ANSWER : : section modulus
31.A prismatic beam of length 1 and fixed at both ends carries a uniformly distributed load. The distance of points of contraflexure from either end is
0.2071
0.2111
0.2771
0.251
ANSWER : : 0.2111
32.The radius of Mohr’s circle for two equal unlike principal stresses of magnitude p is
p
p/2
zero
none of the above
ANSWER : : p
33.A prismatic bar when subjected to pure bending assumes the shape of
catenary
cubic parabola
quadratic parabola
arc of a circle
ANSWER : : arc of a circle
34.The state of pure shear stress is produced by
tension in one direction and equal compression in perpendicular direction
equal tension in two directions at right angles
equal compression in two directions at right angles
none of the above
ANSWER : : tension in one direction and equal compression in perpendicular direction
35.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
1/V3 from left end
1/3 from left end
1/V3 from right end
1/3 from right end
ANSWER : : 1/V3 from left end
36.A beam of overall length 1 with equal overhangs on both sides carries a uniformly distributed load over the entire length. To have numerically equal bending moments at centre of the beam and at supports, the distance between the supports should be
0.2771
0.403 1
0.5861
0.7071
ANSWER : : 0.5861
37.A beam of triangular cross section is placed with its base horizontal. The maximum shear stress intensity in the section will be
at the neutral axis
at the base
above the neutral axis
below the neutral axis
ANSWER : : above the neutral axis
38.According to Rankine’s hypothesis, the criterion of failure of a brittle material is
maximum principal stress
maximum shear stress
maximum strain energy
maximum shear strain energy
ANSWER : : maximum principal stress
39.A portion of a beam between two sections is said to be in pure bending when there is
constant bending moment and zero shear force
constant shear force and zero bending moment
constant bending moment and constant shear force
none of the above
ANSWER : : constant bending moment and zero shear force
40.Of the two prismatic beams of same material, length and flexural strength, one is circular and other is square in cross-section. The ratio of weights of circular and square beams is
1.118
1.342
1.000
0.793
ANSWER : : 1.118
41.The ratio of width to depth of a strongest beam that can be cut out of a cylindrical log of wood is
1/2
1/V2
1/3
2/3
ANSWER : : 1/V2
42.A prismatic beam fixed at both ends carries a uniformly distributed load. The ratio of bending moment at the supports to the bending moment at mid-span is
0.5
1.0
1.5
2.0
ANSWER : : 2.0
43.The difference in ordinate of the shear curve between any two sections is equal to the area under
load curve between these two sections
shear curve between these two sections
bending moment curve between these two sections
load curve between these two sections plus concentrated loads applied between the sections
ANSWER : : load curve between these two sections plus concentrated loads applied between the sections
44.The variation of the bending moment in the portion of a beam carrying linearly varying load is
linear
parabolic
cubic
constant
ANSWER : : cubic
45.A beam of rectangular cross-section is 100 mm wide and 200 mm deep. If the section is subjected to a shear force of 20 kN, then the maximum shear stress in the section is
1 N/mm2
1.125 N/mm2
1.33 N/mm2
1.5 N/mm2
ANSWER : : 1.5 N/mm2
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
between A and C
between C and B
one between A and C and other between C and B
nowhere in the beam
ANSWER : : between A and C
47.The diagram showing the variation of axial load along the span is called
shear force diagram
bending moment diagram
thrust diagram
influence line diagram
ANSWER : : shear force diagram
48.Shear stress on principal planes is
zero
maximum
minimum
none of the above
ANSWER : : zero
49.If the deflection at the free end of a uniformly loaded cantilever beam is 15mm and the slope of the deflection curve at the free end is 0.02 radian, then the length of the beam is
0.8 m
lm
1.2 m
1.5m
ANSWER : : lm
50.A long column has maximum crippling load when its
both ends are hinged
both ends are fixed
one end is fixed and other end is hinged
one end is fixed and other end is free
ANSWER : : both ends are fixed
51.When both ends of a column are fixed, the crippling load is P. If one end of the column is made free, the value of crippling load will be changed to
P/16
P/4
P/2
4P
ANSWER : : P/16
52.A laminated spring is supported at
ends and loaded at centre
centre and loaded at ends
ends and loaded anywhere
centre and loaded anywhere
ANSWER : : centre and loaded at ends
53.Internal forces at every cross-section in a arch are
nornal thrust and shear force
shear force and bending moment
normal thrust and bending moment
normal thrust, shear force and bending moment
ANSWER : : normal thrust, shear force and bending moment
54.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
deflection at D in the first case will be equal to the deflection at C in the second case
deflection at C in the first case is equal to the deflection at D in the second case
deflection at D in the first case will always be smaller than the deflection at C in the second case
deflection at D in the first case will always be greater than the deflection at C in the second case
ANSWER : : deflection at D in the first case will be equal to the deflection at C in the second case
56.A cantilever beam carries a uniformly distributed load from fixed end to the centre of the beam in the first case and a uniformly distributed load of same inten�sity from centre of the beam to the free end in the second case. The ratio of deflections in the two cases is
1/2
3/11
5/24
7/41
ANSWER : : 7/41
57.A beam of overall length / rests on two simple supports with equal overhangs on both sides. Two equal loads act at the free ends. If the deflection at the centre of the beam is the same as at either end, then the length of either overhang is
0 152 1
0.207 1
0.252 1
0.277 1
ANSWER : : 0 152 1
58.Slenderness ratio of a 5 m long column hinged at both ends and having a circular cross-section with diameter 160 mm is
31.25
62.5
100
125
ANSWER : : 125
59.The portion, which should be removed from top and bottom of a circular cross section of diameter d in order to obtain maximum section modulus, is
0.01 d
0.1 d
0.011 d
0.11 d
ANSWER : : 0.011 d
60.Effective length of a chimney of 20 m height is taken as
10 m
20m
28.28m
40m
ANSWER : : 40m
61.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
bending moment
shear force
normal thrust
deflection
ANSWER : : bending moment
62.Buckling load for a given column depends upon
length of column only
least lateral dimension only
both length and least lateral dimension
none of the above
ANSWER : : both length and least lateral dimension
63.For no torsion, the plane of bending should
be parallel to one of the principal axes
pass through shear centre of section
pass through neutral axis of the section
pass through centre of gravity of the section
ANSWER : : pass through shear centre of section
64.Deflection in a leaf spring is more if its
strength is more
strength is less
stiffness is less
stiffness is more
ANSWER : : stiffness is less
65.A laminated spring is given an initial curvature because
it is more economical
it gives uniform strength
spring becomes flat when it is subjec-ted to design load
none of the above
ANSWER : : spring becomes flat when it is subjec-ted to design load
66.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
0.01 radian
0.015 radian
0.02 radian
none of the above
ANSWER : : 0.02 radian
67.If the length of a simply supported beam carrying a concentrated load at the centre is doubled, the defection at the centre will become
two times
four times
eight times
sixteen times
ANSWER : : eight times
68.Rankine’s formula for column is valid when slenderness ratio
lies between 0 and 140
lies between 0 and 100
is less than 80
has any value
ANSWER : : has any value
69.Laminated springs are subjected to
direct stress
bending stress
shear stress
none of the above
ANSWER : : bending stress
70.A simply supported beam with rectangular cross-section is subjected to a central concentrated load. If the width and depth of the beam are doubled, then the deflection at the centre of the beam will be reduced to
50%
25%
12.5%
6.25%
ANSWER : : 6.25%
71.Two beams, one of circular cross-section and other of square cross-section, have equal areas of cross-section. If subjected to bending
circular section is more economical
square section is more economical
both sections are equally strong
both sections are equally stiff
ANSWER : : square section is more economical
72.The effect of arching a beam is
to reduce bending moment throughout
to increase bending moment throughout
to increase shear force
to decrease shear force
ANSWER : : to reduce bending moment throughout
73.Euler’s formula for a mild steel long column hinged at both ends is not valid for slenderness ratio
greater than 80
less than 80
greater than 180
greater than 120
ANSWER : : less than 80
74.In a three hinged arch, the linear and the actual arch meet at
at least three points
at least two points
all points irrespective of loading
nowhere
ANSWER : : at least three points
75.The stress below which a material has a high probability of not failing under reversal of stress is known as
tolerance limit
elastic limit
proportional limit
endurance limit
ANSWER : : elastic limit
76.The specimen in a Charpy impact test is supported as a
cantilever beam
simply supported beam
fixed beam
continuous beam
ANSWER : : simply supported beam
77.Three hinged arch is
statically indeterminate by one degree
statically indeterminate by two degrees
statically determinate
unstable structure
ANSWER : : statically determinate
78.For ductile materials, the most appropriate failure theory is
maximum shear stress theory
maximum principal stress theory
maximum principal strain theory
shear strain energy theory
ANSWER : : maximum shear stress theory
79.If a three hinged parabolic arch carries a uniformly distributed load over the entire span, then any section of the arch is subjected to
normal thrust only
normal thrust and shear force
normal thrust and bending moment
normal thrust, shear force and bending moment
ANSWER : : normal thrust only
80.At a point in a steel member, the major principal stress is 2000 kg/cm2 and the minor principal stress is compressive. If the uni-axial tensile yield stress is 2500 kg/cm2, then the magnitude of the minor principal stress at which yielding will commence, according to the maximum shearing stress theory, is
1000 kg/cm2
2000 kg/cm2
2500 kg/cm2
500 kg/cm2
ANSWER : : 500 kg/cm2
81.For the design of a cast iron member, the most appropriate theory of failure is
Mohr’s theory
Rankine’s theory
Maximum strain theory
Maximum shear energy theory
ANSWER : : Rankine’s theory
82.The basic perfect frame is a
triangle
rectangle
square
hexagon
ANSWER : : triangle
83.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
circular
parabolic
elliptical
none of the above
ANSWER : : parabolic
84.A rectangular block of size 200 mm x 100 mm x 50 mm is subjected to a shear stress of 100 N/mm2. If modulus of rigidity of material is 1 x 105 N/mm2, strain energy stored will be
10 N.m
25 N.m
50 N.m
100N.m
ANSWER : : 50 N.m
85.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
increase definitely
decrease definitely
be difficult to predict
increase or decrease depending upon the radius of the segmental arch
ANSWER : : decrease definitely
86.Impact test enables one to estimate the property of
hardness
toughness
strength
creep
ANSWER : : toughness
87.The property of metal which allows it to deform continuously at slow rate without any further increase in stress is known as
fatigue
creep
plasticity
resilience
ANSWER : : creep
88.Method of joints is applicable only when the number of unknown forces at the joint under consideration is not more than
one
two
three
four
ANSWER : : two
89.A steel rod of cross sectional area equal to 1000 mm2 is 5 m long. If a pull of 100 kN is suddenly applied to it, then the maximum stress intensity will be
50 N/mm2
100 N/mm2
200 N/mm2
400 N/mm2
ANSWER : : 200 N/mm2
90.Proof resilience is the maximum energy stored at
limit of proportionality
elastic limit
plastic limit
none of the above
ANSWER : : elastic limit
91.A short column of external diameter of 250 mm and internal diameter of 150 mm carries an eccentric load of 1000 kN. The greatest eccentricity which the load can have without producing tension anywhere is
20 mm
31.25 mm
37.5 mm
42.5 mm
ANSWER : : 42.5 mm
92.If the depth of a beam of rectangular section is reduced to half, strain energy stored in the beam becomes
1/4 time
1/8 time
4 times
8 times
ANSWER : : 8 times
93.A linear arch has
normal thrust only
shear force only
bending moment only
normal thrust and shear force
ANSWER : : normal thrust only
94.For a determinate pin-jointed plane frame, the relation between the number of joints j and members m is given by
m = 2j – 3
m = 3j-6
m > 2j – 3
m > 3j – 6
ANSWER : : m = 2j – 3
95.Strain energy stored in a member is given by
0.5 x stress x volume
0.5 x strain x volume
0.5 x stress x strain x volume
0.5 x stress x strain
ANSWER : : 0.5 x stress x strain x volume