Theory of Structures MCQ Questions & Answers

Theory of Structures MCQs : This section focuses on the "Theory of Structures". These Multiple Choice Questions (MCQs) should be practiced to improve the Theory of Structures skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.

Question 1

A load of 1960 N is raised at the end of a steel wire. The minimum diameter of the wire so that stress in the wire does not exceed 100 N/mm2 is :

A. 4.0 mm

B. 4.5 mm

C. 5.0 mm

D. 5.5 mm

Question 2

A material is said to be perfectly elastic if

A. it regains its original shape on removal of the load

B. It regains its original shape partially on removal of the load

C. it does not regain its original shape at all

D. none of these.

Question 3

A rolled steel joist is simply supported at its ends and carries a uniformly distributed load which causes a maximum deflection of 10 mm and slope at the ends of 0.002 radian. The length of the joist will be,

A. 10 m

B. 12 m

C. 14 m

D. 16 m

Question 4

A spring of mean radius 40 mm contains 8 action coils of steel (N = 80000 N/mm2), 4 mm in diameter. The clearance between the coils being 1 mm when unloaded, the minimum compressive load to remove the clearance, is

A. 25 N

B. 30 N

C. 35 N

D. 40 N

Question 5

A steel rod 1 metre long having square cross section is pulled under a tensile load of 8 tonnes. The extension in the rod was 1 mm only. If Esteel = 2 x 106 kg/cm2, the side of the rod, is

A. 1 cm

B. 1.5 cm

C. 2 cm

D. 2.5 cm

Question 6

A truss containing j joints and m members, will be a simple truss if

A. m = 2j - 3

B. j = 2m - 3

C. m = 3j - 2

D. j = 3m - 2

Question 7

Beams composed of more than one material, rigidly connected together so as to behave as one piece, are known as

A. Compound beams

B. Indeterminate beams

C. Determinate beams

D. Composite beams.

Question 8

For determining the support reactions at A and B of a three hinged arch, points B and C are joined and produced to intersect the load line at D and a line parallel to the load line through A at D'. Distances AD, DD' and AD' when measured were 4 cm, 3 cm and 5 cm respectively. The angle between the reactions at A and B is

A. 30°

B. 45°

C. 60°

D. 90°

Question 9

If ΣH and ΣV are the algebraic sums of the forces resolved horizontally and vertically respectively, and ΣM is the algebraic sum of the moments of forces about any point, for the equilibrium of the body acted upon

A. ΣH = 0

B. ΣV = 0

C. ΣM = 0

D. all the above.

Question 10

If Q is load factor, S is shape factor and F is factor of safety in elastic design, the following:

A. Q = S + F

B. Q = S - F

C. Q = F - S

D. Q = S x F

Question 11

In plastic analysis, the shape factor for a circular section, is

A. 1.5

B. 1.6

C. 1.7

D. 1.75

Question 12

In plastic analysis, the shape factor for a triangular section, is

A. 1.5

B. 1.34

C. 2.34

D. 2.5

Question 13

In plastic analysis, the shape factor for rectangular section, is

A. 1.4

B. 1.5

C. 1.6

D. 1.7

Question 14

Keeping the depth d constant, the width of a cantilever of length l of uniform strength loaded with a uniformly distributed load w varies from zero at the free end and

A. at the fixed end

B. at the fixed end

C. at the fixed end

D. at the fixed end

Question 15

Pick up the correct statement from the following:

A. Hoop strain of the walls of a cylinder due to liquid is

B. Longitudinal strain in the walls of a cylinder due to liquid is

C. Volumetric change in the cylinderdue to liquid is

D. All the above.

Question 16

Pick up the incorrect statement from the following : The torsional resistance of a shaft is directly proportional to

A. modulus of rigidity

B. angle of twist

C. reciprocal of the length of the shaft

D. moment of inertia of the shaft section.

Question 17

Principal planes are subjected to

A. normal stresses only

B. tangential stresses only

C. normal stresses as well as tangential stresses

D. none of these.

Question 18

Stress may be defined as

A. force per unit length

B. force per unit volume

C. force per unit area

D. none of these.

Question 19

Stress may be expressed in Newtons

A. per millimetre square (N/mm2)

B. per centimetre square (N/cm2)

C. per metre square (N/m2)

D. All of the above.

Question 20

The normal component of a force inclined through θ° is obtained by multiplying the force by

A. sin θ

B. cos θ

C. tan θ

D. sin θ cos θ

Question 21

The point of contraflexure is the point where

A. B.M. changes sign

B. B.M. is maximum

C. B.M. is minimum

D. S.F. is zero.

Question 22

The shape factor of standard rolled beam section varies from

A. 1.10 to 1.20

B. 1.20 to 1.30

C. 1.30 to 1.40

D. 1.40 to 1.50

Question 23

There are two hinged semicircular arches A, B and C of radii 5 m, 7.5 m and 10 m respectively and each carries a concentrated load W at their crowns. The horizontal thrust at their supports will be in the ratio of

A. 1 : 1 1/2 : 2

B. 2 : 1 1/2 : 1

C. 01:01:02

D. none of these.

Question 24

Total strain energy theory for the failure of a material at elastic limit, is known

A. Guest's or Trecas' theory

B. St. Venant's theory

C. Rankine's theory

D. Haig's theory

Question 25

A simply supported beam A carries a point load at its mid span. Another identical beam B carries the same load but uniformly distributed over the entire span. The ratio of the maximum deflections of the beams A and B, will be

A. 2-3

B. 3-2

C. 5-8

D. 8-5

Question 26

Principal planes are subjected to

A. Normal stresses only

B. Tangential stresses only

C. Normal stresses as well as tangential stresses

D. None of these

Question 27

Y are the bending moment, moment of inertia, radius of curvature, modulus of If M, I, R, E, F, and elasticity stress and the depth of the neutral axis at section, then

A. M/I = R/E = F/Y

B. I/M = R/E = F/Y

C. M/I = E/R = F/Y

D. M/I = E/R = Y/F

Question 28

A shaft is subjected to bending moment M and a torque T simultaneously. The ratio of the maximum bending stress to maximum shear stress developed in the shaft, is

A. M/T

B. T/M

C. 2M/ T

D. 2T/M

Question 29

A masonry dam (density = 20,000 N/m³) 6 m high, one metre wide at the top and 4 m wide at the base, has vertical water face. The minimum stress at the base of the dam when the reservoir is full, will be

A. 75 N/m²

B. 750 N/m²

C. 7500 N/m²

D. 75000 N/m²

Question 30

The ratio of the maximum deflections of a simply supported beam with a central load W and of a cantilever of same length and with a load W at its free end, is

A. 1-8

B. 1-10

C. 1-12

D. 1-16

Question 31

The ratio of the length and depth of a simply supported rectangular beam which experiences maximum bending stress equal to tensile stress, due to same load at its mid span, is

A. 1-2

B. 2-3

C. 1-4

D. 1-3

Question 32

The ratio of the length and diameter of a simply supported uniform circular beam which experiences maximum bending stress equal to tensile stress due to same load at its mid span, is

A. 1-8

B. 1-4

C. 1-2

D. 1-3

Question 33

a uniform circular bar of diameter d and length , which extends by an The deflection of amount under a tensile pull , when it carries the same load at its mid-span, is

A. el/2d

B. e²l/3d²

C. el²/3d²

D. e²l²/3d²

Question 34

A three hinged arch is generally hinged at its supports and

A. At one quarter span

B. At the crown

C. Anywhere in the rib

D. None of these

Question 35

Shear strain energy theory for the failure of a material at elastic limit, is due to

A. Rankine

B. Guest or Trecas

C. St. Venant

D. Von Mises

Question 36

The maximum magnitude of shear stress due to shear force F on a rectangular section of area A at the neutral axis, is

A. F/A

B. F/2A

C. 3F/2A

D. 2F/3A

Question 37

A simply supported rolled steel joist 8 m long carries a uniformly distributed load over it span so that the maximum bending stress is 75 N/mm². If the slope at the ends is 0.005 radian and the value of E = 0.2 × 106 N/mm², the depth of the joist, is

A. 200 mm

B. 250 mm

C. 300 mm

D. 400 mm

Question 38

A short column (30 cm × 20 cm) carries a load P 1 at 4 cm on one side and another load P2at 8 cm on the other side along a principal section parallel to longer dimension. If the extreme intensity on either side is same, the ratio of P1 to P2 will be

A. 2-3

B. 3-2

C. 8-5

D. 5-8

Question 39

A compound truss may be formed by connecting two simple rigid frames, by

A. Two bars

B. Three bars

C. Three parallel bars

D. Three bars intersecting at a point

Question 40

If a three hinged parabolic arch, (span l, rise h) is carrying a uniformly distributed load w/unit length over the entire span,

A. Horizontal thrust is wl2/8h

B. S.F. will be zero throughout

C. B.M. will be zero throughout

D. All the above

Question 41

constant, depth of a cantilever of length of uniform strength loaded with Keeping breadth uniformly distributed load varies from zero at the free end and

A. 2w w l at the fixed end

B. l) at the fixed end

C. w l) at the fixed end

D. 3w l at the fixed end

Question 42

A cantilever of length ‘L’ is subjected to a bending moment ‘M’ at its free end. If EI is the flexural rigidity of the section, the deflection of the free end, is

A. ML/EI

B. ML/2EI

C. ML²/2EI

D. ML²/3EI

Question 43

A cantilever of length 2 cm and depth 10 cm tapers in plan from a width 24 cm to zero at its free end. If the modulus of elasticity of the material is 0.2 × 106 N/mm², the deflection of the free end, is

A. 2 mm

B. 3 mm

C. 4 mm

D. 5 mm

Question 44

In the truss, the force in the member AC is

A. 6.25 t compressive

B. 8.75 t tensile

C. t tensile

D. t compressive

Question 45

If a concrete column 200 × 200 mm in cross-section is reinforced with four steel bars of 1200 mm² total cross-sectional area. Calculate the safe load for the column if permissible stress in concrete is 5 N/mm² and Es is 15 Ec

A. 264 MN

B. 274 MN

C. 284 MN

D. 294 MN

Question 46

Slenderness ratio of a long column, is

A. Area of cross-section divided by radius of gyration

B. Area of cross-section divided by least radius of gyration

C. Radius of gyration divided by area of cross-section

D. Length of column divided by least radius of gyration

Question 47

The ratio of the area of cross-section of a circular section to the area of its core, is

A. 4

B. 8

C. 12

D. 16

Question 48

A truss containing j joints and m members, will be a simple truss if

A. m = 2j – 3

B. j = 2m – 3

C. m = 3j – 2

D. j = 3m – 2

Question 49

For beams breadth is constant,

A. Depth d M

B. Depth d 3

C. Depth d

D. Depth d 1/M

Question 50

Flat spiral springs

A. Consist of uniform thin strips

B. Are supported at outer end

C. Are wound by applying a torque

D. All the above

Question 51

The ratio of lateral strain to axial strain of a homogeneous material, is known

A. Yield ratio

B. Hooke’s ratio

C. Poisson’s ratio

D. Plastic ratio

Question 52

A steel rod of sectional area 250 sq. mm connects two parallel walls 5 m apart. The nuts at the ends were tightened when the rod was heated to 100°C. If steel = 0.000012/C°, Esteel = 0.2 MN/mm², the tensile force developed at a temperature of 50°C, is

A. 80 N/mm²

B. 100 N/mm 2

C. 120 N/mm²

D. 150 N/mm²

Question 53

In case of principal axes of a section

A. Sum of moment of inertia is zero

B. Difference of moment inertia is zero

C. Product of moment of inertia is zero

D. None of these

Question 54

A close coil helical spring when subjected to a moment M having its axis along the axis of the helix

A. It is subjected to pure bending

B. Its mean diameter will decrease

C. Its number of coils will increase

D. All the above

Question 55

The forces in the members of simple trusses, may be analysed by

A. Graphical method

B. Method of joints

C. Method of sections

D. All the above

Question 56

The moment of inertia of a triangular section (height h, base b) about its base, is

A. bh²/12

B. b²h/12

C. bh³/12

D. b³h/12

Question 57

Maximum shear stress theory for the failure of a material at the elastic limit, is known

A. Guest's or Trecas' theory

B. St. Venant's theory

C. Rankine's theory

D. Haig's theory

Question 58

Total strain energy theory for the failure of a material at elastic limit, is known

A. Guest’s or Trecas’ theory

B. St. Venant’s theory

C. Rankine’s theory

D. Haig’s theory

Question 59

Maximum principal stress theory for the failure of a material at elastic point, is known

A. Guest's or Trecas' theory

B. St. Venant's theory

C. Rankine's theory

D. Von Mises' theory

Question 60

The locus of reaction of a two hinged semi-circular arch, is

A. Straight line

B. Parabola

C. Circle

D. Hyperbola

Question 61

The ratio of maximum shear stress to average shear stress of a circular beam, is

A. 2-3

B. 3-2

C. 3-4

D. 4-3

Question 62

P = 4π² EI/L² is the equation of Euler's crippling load if

A. Both the ends are fixed

B. Both the ends are hinged

C. One end is fixed and other end is free

D. One end is fixed and other end is hinged

Question 63

The ratio of the deflections of the free end of a cantilever due to an isolated load at 1/3rd and 2/3rd of the span, is

A. 1-7

B. 2-7

C. 3-7

D. 2-5

Question 64

A steel rod 1 metre long having square cross section is pulled under a tensile load of 8 tonnes. The extension in the rod was 1 mm only. If Esteel = 2 × 106 kg/cm², the side of the rod, is

A. 1 cm

B. 1.5 cm

C. 2 cm

D. 2.5 cm

Question 65

The assumption in the theory of bending of beams is:

A. Material is homogeneous

B. Material is isotropic

C. Young’s modulus is same in tension as well as in compression

D. All the above

Question 66

The maximum deflection of a simply supported beam of span L, carrying an isolated load at the centre of the span; flexural rigidity being EI, is

A. WL3/3EL

B. WL3/8EL

C. WL3/24EL

D. WL3/48EL

Question 67

The horizontal thrust on the ends of a two hinged semicircular arch of radius ‘R’ carrying

A. A uniformly distributed load ? per unit run over its right half span, is ? ?R/?

B. A uniformly distributed load ? per unit run over its entire span is 4/3 ?R/?

C. A distributed load varying from zero at the left end to ? per unit horizontal run at the right end, is ? ?R/?

D. All the above

Question 68

For a strongest rectangular beam cut from a circular log, the ratio of the width and depth, is

A. 0.303

B. 0.404

C. 0.505

D. 0.707

Question 69

H V are the algebraic sums of the forces resolved horizontally and vertically respectively, M is the algebraic sum of the moments of forces about any point, for the equilibrium of the body acted upon

A. H = 0

B. V = 0

C. M = 0

D. All the above

Question 70

The ratio of crippling loads of a column having both the ends fixed to the column having both the ends hinged, is

A. 1

B. 2

C. 3

D. 4

Question 71

The equivalent length of a column of length L, having both the ends hinged, is

A. 2L

B. L

C. L/2

D. L/√2

Question 72

There are two hinged semicircular arches A, B and C of radii 5 m, 7.5 m and 10 m respectively and each carries a concentrated load W at their crowns. The horizontal thrust at their supports will be in the ratio of

A. 1 : 1½ : 2

B. 2 : 1½ : 1

C. 1 : 1 : 2

D. None of these

Question 73

Gradually applied static loads do not change with time their

A. Magnitude

B. Direction

C. Point of application

D. All the above

Question 74

The yield moment of a cross section is defined as the moment that will just produce the yield stress in

A. The outer most fibre of the section

B. The inner most fibre of the section

C. The neutral fibre of the section

D. The fibre everywhere

Question 75

Beams composed of more than one material, rigidly connected together so as to behave as one piece, are known as

A. Compound beams

B. Indeterminate beams

C. Determinate beams

D. Composite beams

Question 76

At yield point of a test piece, the material

A. Obeys Hooke’s law

B. Behaves in an elastic manner

C. Regains its original shape on removal of the load

D. Undergoes plastic deformation

Question 77

The load on a spring per unit deflection, is called

A. Stiffness

B. Proof resilience

C. Proof stress

D. Proof load

Question 78

A steel bar 20 mm in diameter simply-supported at its ends over a total span of 40 cm carries a load at its centre. If the maximum stress induced in the bar is limited to N/mm², the bending strain energy stored in the bar, is

A. 411 N mm

B. 511 N mm

C. 611 N mm

D. 711 N mm

Question 79

A load of 1960 N is raised at the end of a steel wire. The minimum diameter of the wire so that stress in the wire does not exceed 100 N/mm² is:

A. 4.0 mm

B. 4.5 mm

C. 5.0 mm

D. 5.5 mm

Question 80

For beams of uniform strength, if depth is constant,

A. Width b M

B. Width b M

C. Width b 3 M

D. Width b 1/M

Question 81

A composite beam is composed of two equal strips one of brass and other of steel. If the temperature is raised

A. Steel experiences tensile force

B. Brass experiences compressive force

C. Composite beam gets subjected to a couple

D. All the above

Question 82

A compound bar consists of two bars of equal length. Steel bar cross -section is 3500 mm²and that of brass bar is 3000 mm². These are subjected to a compressive load 100,000 N. If Eb = 0.2 MN/mm² and Eb = 0.1 MN/mm², the stresses developed are:

A. b = 10 N/mm² s = 20 N/mm 2

B. b = 8 N/mm² s = 16 N/mm²

C. b = 6 N/mm² s = 12 N/mm²

D. b = 5 N/mm² s = 10 N/mm²

Question 83

A material is said to be perfectly elastic if

A. It regains its original shape on removal of the load

B. It regains its original shape partially on removal of the load

C. It does not regain its original shape at all

D. None of these

Question 84

Pick up the correct statement from the following:

A. The moment of inertia is calculated about the axis about which bending takes place

B. If tensile stress is less than axial stress, the section experiences compressive stress

C. If tensile stress is equal to axial stress, the section experiences compressive stress

D. All the above

Question 85

For calculating the allowable stress of long columns σ0 = σy/n [1 - a (1/r)²]is the empirical formula, known as

A. Straight line formula

B. Parabolic formula

C. Perry

D. Rankine

Question 86

The ratio of maximum and average shear stresses on a rectangular section, is

A. 1

B. 1.25

C. 1.5

D. 2.5

Question 87

A simply supported beam which carries a uniformly distributed load has two equal overhangs. To have maximum B.M. produced in the beam least possible, the ratio of the length of the overhang to the total length of the beam, is

A. 0.207

B. 0.307

C. 0.407

D. 0.508

Question 88

section modulus of a square section of side B and that of a circular section of the ratio of the diameter D, is

A. 2 /15

B. 3 /16

C. 3 /8

D. /16

Question 89

A simply supported uniform rectangular bar breadth b, depth d and length L carries an isolated load W at its mid-span. The same bar experiences an extension e under same tensile load. The ratio of the maximum deflection to the elongation, is

A. L/d

B. L/2d

C. (L/2d)²

D. (L/3d)²

Question 90

The equivalent length is of a column of length having both the ends fixed, is

A. 2 L

B. L

C. L/2

D. L

Question 91

Pick up the correct statement from the following:

A. Hoop strain of the walls of a cylinder due to liquid is (pd/2tE) (1 – 1/2m)

B. Longitudinal strain in the walls of a cylinder due to liquid is (pd/2 tE) (1/2 – 1/m)

C. Volumetric change in the cylinder due to liquid is (pd/2tE) (5/2 – 2/m)

D. All the above

Question 92

A shaft rotating N.R.M. under a torque T, transmits a power

A. /30 Newton metres/sec

B. /30 Newton metres/min

C. /60 Newton metres/min

D. /60 Newton metres/sec

Question 93

A shaft subjected to a bending moment M and a torque T, experiences

A. Maximum bending stress = 32M/πd³

B. Maximum shear stress = 16 T/πd³

C. Both A and B

D. Neither A nor B

Question 94

The strain energy due to volumetric strain

A. Is directly proportional to the volume

B. Is directly proportional to the square of exerted pressure

C. Is inversely proportional to Bulk modulus

D. All the above

Question 95

The maximum bending moment for a simply supported beam with a uniformly distributed load w/unit length, is

A. WI/2

B. WI²/4

C. WI²/8

D. WI²/12

Question 96

The general expression for the B.M. of a beam of length l is the beam carries M = (wl/2) x – (wx²/2)

A. A uniformly distributed load w/unit length

B. A load varying linearly from zero at one end to w at the other end

C. An isolated load at mid span

D. None of these

Question 97

Pick up the incorrect statement from the following: The torsional resistance of a shaft is directly proportional to

A. Modulus of rigidity

B. Angle of twist

C. Reciprocal of the length of the shaft

D. Moment of inertia of the shaft section

Question 98

In a shaft, the shear stress is not directly proportional to

A. Radius of the shaft

B. Angle of twist

C. Length of the shaft

D. Modulus of rigidity

Question 99

The stiffness of the close coil helical spring is

A. d4N/8D3n

B. d4N/4D3n

C. 4D3N/d4n

D. 8D3N/d4n

Question 100

Pick up the correct statement from the following:

A. In a loaded beam, the moment at which the first yield occurs is called yield moment

B. In a loaded beam, the moment at which the entire section of the beam becomes fully plastic, is called plastic moment

C. In a fully plastic stage of the beam, the neutral axis divides the section in two sections of equal area

D. All the above

Question 101

Maximum strain theory for the failure of a material at the elastic limit, is known as

A. Guest's or Trecas' theory

B. St. Venant's theory

C. Rankine's theory

D. Haig's theory

Question 102

A body is said to be in equilibrium if

A. It moves horizontally

B. It moves vertically

C. It rotates about its C.G.

D. None of these

Question 103

A close coil helical spring of mean diameter D consists of n coils of diameter d. If it carries an axial load W, the energy stored in the spring, is

A. 4WD²n/d4N

B. 4W²Dn/d4N

C. 4W²D3n/d4N

D. 4W²D3n²/d4N

Question 104

A two hinged parabolic arch of span l and rise h carries a load varying from zero at the left end to ? per unit run at the right end. The horizontal thrust is

A. ωl²/4h

B. ωl²/8h

C. ωl²/12h

D. ωl²/16h

Question 105

The maximum deflection due to a load W at the free end of a cantilever of length L and having flexural rigidity EI, is

A. WL²/2EI

B. WL²/3EI

C. WL3/2EI

D. WL3/3EI

Question 106

The ratio of moments of inertia of a triangular section about its base and about a centroidal axis parallel to its base, is

A. 1

B. 1.5

C. 2

D. 3

Question 107

Inertia of a rectangular section of width and depth about an axis passing the moment of through C.G. and parallel to its width is

A. BD²/6

B. BD³/6

C. BD³/12

D. B²D/6

Question 108

The ratio of the stresses produced by a suddenly applied load and by a gradually applied load on a bar, is

A. 1-4

B. 1-2

C. 1

D. 2

Question 109

The ratio of circumferential stress to the longitudinal stress in the walls of a cylindrical shell, due to flowing liquid, is

A. ½

B. 1

C. 1½

D. 2

Question 110

Stress may be defined as

A. Force per unit length

B. Force per unit volume

C. Force per unit area

D. None of these

Question 111

A steel bar 5 m × 50 mm is loaded with 250,000 N. If the modulus of elasticity of the material is 0.2 MN/mm² and Poisson’s ratio is 0.25, the change in the volume of the bar is:

A. 1.125 cm³

B. 2.125 cm³

C. 3.125 cm³

D. 4.125 cm²

Question 112

For the close coil helical spring of the maximum deflection is

A. WD3n/d4N

B. 2WD3n/d4N

C. 4W²D3n/d4N

D. 8WD3n/d4N

Question 113

The vertical reaction for the arch is

A. wa/2l

B. wl/a

C. wa/l

D. wa²/2l

Question 114

Pick up the correct statement from the following:

A. For a uniformly distributed load, the shear force varies linearly

B. For a uniformly distributed load, B.M. curve is a parabola

C. For a load varying linearly, the shear force curve is a parabola

D. All the above

Question 115

If Q is load factor, S is shape factor and F is factor of safety in elastic design, the following:

A. Q = S + F

B. Q = S – F

C. Q = F – S

D. Q = S × F

Question 116

The locus of the end point of the resultant of the normal and tangential components of the stress on an inclined plane, is

A. Circle

B. Parabola

C. Ellipse

D. Straight line

Question 117

A simply supported beam carries varying load from zero at one end and w at the other end. If the length of the beam is a, the maximum bending moment will be

A. wa/27

B. wa²/27

C. w²a

D. wa²

Question 118

A square column carries a load P at the centroid of one of the quarters of the square. If a is the side of the main square, the combined bending stress will be

A. p/a²

B. 2p/a²

C. 3p/a²

D. 4p/a²

Question 119

The eccentricity (e) of a hollow circular column, external diameter 25 cm, internal diameter 15 cm for an eccentric load 100 t for non-development of tension, is

A. 2.75 cm

B. 3.00 cm

C. 3.50 cm

D. 4.25 cm

Question 120

At any point of a beam, the section modulus may be obtained by dividing the moment of inertia of the section by

A. Depth of the section

B. Depth of the neutral axis

C. Maximum tensile stress at the section

D. Maximum compressive stress at the section

Question 121

Pick up the correct statement from the following:

A. The structural member subjected to compression and whose dimensions are small as compared to its length, is called a stmt

B. The vertical compression members are generally known as columns or stanchions

C. Deflection in lateral direction of a long column, is generally known as buckling

D. All the above

Question 122

For determining the support reactions at A and B of a three hinged arch, points B and Care joined and produced to intersect the load line at D and a line parallel to the load line through A at D’. Distances AD, DD’ and AD’ when measured were 4 cm, 3 cm and 5 cm respectively. The angle between the reactions at A and B is

A. 30°

B. 45°

C. 60°

D. 90°

Question 123

If E, N, K and 1/m are modulus of elasticity, modulus of rigidity. Bulk modulus and Poisson ratio of the material, the following relationship holds good

A. E = 3K (1 – 2/m)

B. E = 2N (1 + 1/m)

C. (3/2)K (1 – 2/m) = N (1 + 1/m)

D. All the above

Question 124

The horizontal deflection of a parabolic curved beam of span 10 m and rise 3 m when loaded with a uniformly distributed load l t per horizontal length is (where Ic is the M.I. at the crown, which varies as the slope of the arch).

A. 50/EIc

B. 100/EIc

C. 150/EIc

D. 200/EIc

Question 125

In case of a simply supported rectangular beam of span L and loaded with a central load W, the length of elasto-plastic zone of the plastic hinge, is

A. L/2

B. L/3

C. L/4

D. L/5

Question 126

In case of a simply supported I-section beam of span L and loaded with a central load W, the length of elasto-plastic zone of the plastic hinge, is

A. L/2

B. L/3

C. L/4

D. L/5

Question 127

A bar L metre long and having its area of cross-section A, is subjected to a gradually applied tensile load W. The strain energy stored in the bar is

A. WL/2AE

B. WL/AE

C. W²L/AE

D. W²L/2AE

Question 128

Stress may be expressed in Newtons

A. Per millimetre square (N/mm²)

B. Per centimetre square (N/cm²)

C. Per metre square (N/m2)

D. None of these

Question 129

Pick up the correct statement from the following:

A. For channels, the shear centre does not coincide its centroid

B. The point of intersection of the bending axis with the cross section of the beam, is called shear centre

C. For I sections, the shear centre coincides with the centroid of the cross section of the beam

D. All the above

Question 130

The locus of the moment of inertia about inclined axes to the principal axis, is

A. Straight line

B. Parabola

C. Circle

D. Ellipse

Question 131

The point of contraflexure is the point where

A. B.M. changes sign

B. B.M. is maximum

C. B.M. is minimum

D. S.F. is zero

Question 132

A lift of weight W is lifted by a rope with an acceleration f. If the area of cross-section of the rope is A, the stress in the rope is

A. [W (1 + f/ G)]/ A

B. (1 – g/f)/A

C. [W (2 + f/G)]/A

D. [W (2 + g/f)]/A

Question 133

If a solid shaft (diameter 20 cm, length 400 cm, N = 0.8 × 105 N/mm²) when subjected to a twisting moment, produces maximum shear stress of 50 N/mm 2, the angle of twist in radians, is

A. 0.001

B. 0.002

C. 0.0025

D. 0.003

Question 134

The ratio of shear stress and shear strain of an elastic material, is

A. Modulus of Rigidity

B. Shear Modulus

C. Modulus of Elasticity

D. Both A. and B.

Question 135

A steel plate d × b is sandwiched rigidly between two timber joists each D × B/2 in section. The steel will be (where Young’s modulus of steel is m times that of the timber).

A. BD² + mbd²)/6D]

B. BD³ + mbd³)/6D]

C. BD² + mbd³)/4D]

D. BD² + mbd²)/4D]

Question 136

An isolated load W is acting at a distance a from the left hand support, of a three hinged arch of span 2l and rise h hinged at the crown, the horizontal reaction at the support, is

A. Wa/h

B. Wa/2h

C. 2W/ha

D. 2h/Wa

Question 137

A spring of mean radius 40 mm contains 8 action coils of steel (N = 80000 N/mm²), 4 mm in diameter. The clearance between the coils being 1 mm when unloaded, the minimum compressive load to remove the clearance, is

A. 25 N

B. 30 N

C. 35 N

D. 40 N

Question 138

parabolic arch of span and rise , is given by The equation of a

A. y = h/l² × (1 – x )

B. y = 2h/l² × (1 – x)

C. y = 3h/l² × (1 – x)

D. y = 4h/l² × (1 – x)

Question 139

The equivalent length of a column of length L having one end fixed and the other end free, is

A. 2L

B. L

C. L/2

D. L

Question 140

Pick up the correct statement from the following:

A. A wire wound in spiral form, is called a helical spring

B. The pitch of a close coil spring, is very small

C. The angle made by the coil with horizontal, is called the angle of helix

D. All the above

Question 141

The area of the core of a column of cross sectional area A, is

A. (1/3) A

B. (1/6) A

C. (1/12) A

D. (1/18) A

Question 142

The strain energy stored in a spring when subjected to greatest load without being permanently distorted, is called

A. Stiffness

B. Proof resilience

C. Proof stress

D. Proof load

Question 143

The greatest load which a spring can carry without getting permanently distorted, is called

A. Stiffness

B. Proof resilience

C. Proof stress

D. Proof load