GATE - CE - Strength of Materials

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    GATE CE Topic wise Questions

    Strength of Materials

    www.gatehelp.com

    YEAR 2009 ONE MARK

    Question. 1

    A thin walled cylindrical pressure vessel having a radius of 0.5 m and

    wall thickness of 25 mm is subjected to an internal pressure of 700

    kPa. The hoop stress developed is

    (A) 14 MPa (B) 1.4 MPa

    (C) 0.14 MPa (D) 0.014 MPa

    Question. 2

    The point within the cross sectional plane of a beam through which

    the resultant of the external loading on the beam has to pass through

    to ensure pure bending without twisting of the cross-section of the

    beam is called

    (A) moment centre (B) centroid

    (C) shear centre (D) elastic center

    YEAR 2009 TWO MARK

    Question. 3

    Consider the following statements :

    1. On a principal plane, only normal stress acts.

    2. On a principal plane, both normal and shear stresses act.

    3. On a principal plane, only shear stress acts

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    4. Isothermal state of stress is independent of frame of reference.

    Which of the above statements is/are correct ?

    (A) 1 and 4 (B) 2 only

    (C) 2 and 4 (D) 2 and 3

    Question. 4

    A hollow circular shaft has an outer diameter of 100 mm and a wall

    thickness of 25 mm. The allowable shear stress in the shaft is 125

    MPa. The maximum torque the shaft can transmit is

    (A) 46 kNm (B) 24.5 kNm

    (C) 23 kNm (D) 11.5 kNm

    Question. 5

    Match List-I (Shear Force Diagrams) beams with List-II (Diagram of

    beams with supports and loading) and select the correct answer by

    using the codes given below the lists :

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    Codes :

    a b c d

    (A) 3 1 2 4

    (B) 3 4 2 1

    (C) 2 1 4 3

    (D) 2 4 3 1

    Statement for Linked Answer Questions 6 & 7 :

    In the cantilever beam PQR shown in figure below, the segment PQ

    has flexural rigidity EI and the segment QR has infinite flexural

    rigidity

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    Question. 6

    The deflection and slope of the beam at Q are respectively

    (A)6

    52

    3EI

    andWLEI

    WL3 2 (B)

    3 2EIandWL

    EIWL3 2

    (C)2EI

    andWLEI

    WL3 2 (D)

    3 23

    EIandWL

    EIWL3 2

    Question. 7

    The deflection of the beam at R is

    (A) 8EIWL3

    (B) 56EIWL3

    (C)3

    7EI

    WL3 (D) 86EIWL3

    YEAR 2008 ONE MARK

    Question. 8

    A mild steel specimen is under uniaxial tensile stress. Youngs

    modulus and yield stress for mild steel are 2 105# MPa and 250

    MPa respectively. The maximum amount of strain energy per unit

    volume that can be stored in this specimen without permanent set is

    (A) 156 Nmm/mm3 (B) 15.6 Nmm/mm3

    (C) 1.56 Nmm/mm3 (D) 0.156 Nmm/mm3

    YEAR 2008 TWO MARK

    Question. 9

    Cross-section of a column consisting to two steel strips, each of

    thickness t and width b is shown in the figure below. The critical

    loads of the column with perfect bond and without bond between the

    strips are P and P0 respectively. The ratio /P P0 is

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    (A) 2 (B) 4

    (C) 6 (D) 8

    Question. 10

    A rigid bar GH of length L is supported by a hinge and a spring of

    stiffness K as shown in the figure below. The buckling load, Pcr, for

    the bar will be

    (A) 0.5KL (B) 0.8KL

    (C) 1.0KL (D) 1.2KL

    Question. 11

    The maximum shear stress in a solid shaft of circular cross-section

    having diameter d subjected to a subject to a torque T is . If the

    torque is increased by four times and the diameter of the shaft is

    increased by two times, the maximum shear stress in the shaft will be

    (A) 2 (B)

    (C) /2 (D) /4

    Question. 12

    A vertical rod PQ of length L is fixed at its top end P and has a

    flange fixed to the bottom end Q. A weight W is dropped vertically

    from a height ( )h L< on to the flange. The axial stress in the rod can

    be reduced by

    (A) increasing the length of the rod

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    (B) decreasing the length of the rod

    (C) decreasing the area of cross-section of the rod

    (D) increasing the modulus of elasticity of the material

    Question. 13

    The maximum tensile stress at the section X-X shown in the figure

    below is

    (A)bd

    P8 (B)

    bdP6

    (C)bd

    P4 (D)

    bdP2

    Question. 14

    The stepped cantilever is subjected to moments, M as shown in the

    figure below. The vertical deflection at the free end (neglecting the

    self weight) is

    (A)8EIML2

    (B)4EIML2

    (C)EI

    ML2 (D) Zero

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    Statement for Linked Answer Questions 15 & 16 :

    Beam GHI is supported by three pontoons as shown in the figure

    below. The horizontal cross-sectional area of each pontoon is 8 m2,

    the flexural rigidity of the beam is 10000 kNm2 and the unit weightof water is 10 kNm3

    Question. 15

    When the middle pontoon is removed, the deflection at H will be

    (A) 0.2 m (B) 0.4 m

    (C) 0.6 m (D) 0.8 m

    Question. 16

    When the middle pontoon is brought back to its position as shown in

    the figure above, the reaction at H will be

    (A) 8.6 kN (B) 15.7 kN

    (C) 19.2 kN (D) 24.2 kN

    YEAR 2007 ONE MARK

    Question. 17

    An axially loaded bar is subjected to a normal stress os 173 MPa.

    The stress in the bar is

    (A) 75 MPa (B) 86.5 MPa

    (C) 100 MPa (D) 122.3 MPa

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    Question. 18

    A steel column, pinned at both end, has a buckling load of 200 kN. If

    the column is restrained against lateral movement at its mid-height,

    it buckling load will be

    (A) 200 kN (B) 283 kN

    (C) 400 kN (D) 800 kN

    Question. 19

    For an isotropic material, the relationship between the Youngs

    modulus (E), shear modulus (G) and Poissons ratio () is given by

    (A)( )

    G E2 1

    =+

    (B)( )

    E E2 1

    =+

    (C)( )

    GE

    1 2=

    +(D)

    ( )G

    E2 1 2

    =

    YEAR 2007 TWO MARK

    Question. 20

    A metal bar of length 100 mm is inserted between two rigid supports

    and its temperature is increased by 10 Cc . If the coefficient of thermal

    expansion is 12 10 per C6# c and the Youngs modulus is 2 105#

    MPa, the stress in the bar is

    (A) zero (B) 12 MPa

    (C) 24 MPa (D) 2400 MPa

    Question. 21

    A rigid bar is suspended by three rods made of the same material as

    shown in the figure. The area and length of the central rod are 3 A

    and L, respectively while that of the two outer rods are A2 and L2 ,

    respectively. If a downward force of 50 kN is applied to the rigid bar,

    the forces in the central and each of the outer rods will be

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    (A) 16.67 kN each (B) 30 kN and 15 kN

    (C) 30 kN and 10 kN (D) 21.4 kN and 14.3 kN

    Question. 22

    The maximum and minimum shear stresses in a hollow circular shaft

    of outer diameter 20 mm and thickness 2 mm, subjected to a torque

    of 92.7 Nm will be

    (A) 59 MPa and 47.2 MPa (B) 100 MPa and 80 MPa

    (C) 118 MPa and 160 MPa (D) 200 MPa and 160 MPa

    Question. 23

    The shear stress at the neutral axis in a beam of triangular section

    with a base of 40 mm and height 20 mm, subjected to a shear force

    of 3 kN is

    (A) 3 MPa (B) 6 MPa

    (C) 10 MPa (D) 20 MPa

    Question. 24

    U1 and U2 are the strain energies stored in a prismatic bar due to axial

    tensile forces P1 and P2, respectively. The strain energy U stored in

    the same bar due to combined action ofP1 and P2 will be

    (A) U U U1 2= + (B) U U U1 2=

    (C) U U U< 1 2+ (D) U U U> 1 2+

    YEAR 2006 ONE MARK

    Question. 25

    Mohrs circle for the state of stress defined by30

    0

    0

    30> H MPa is a circle

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    with

    (A) centre at (0, 0) and radius 30 MPa

    (B) centre at (0, 0) and radius 60 MPa

    (C) centre at (30, 0) and radius 30 MPa(D) centre at (30, 0) and zero radius

    Question. 26

    A long shaft of diameter d is subjected to twisting moment T at its

    ends. The maximum normal stress acting at its cross-section is equal

    to

    (A) zero (B)dT163

    (C)dT32 3

    (DdT64 3

    Question. 27

    The buckling load P Pcr= for the column AB in figure, as KT

    approaches infinity, becomesLEI2

    2

    Where is equal to

    (A) 0.25 (B) 1.00

    (C) 2.05 (D) 4.00

    YEAR 2006 TWO MARKS

    Question. 28

    A thin-walled long cylindrical tank is inside radius r is subjected

    simultaneously to internal gas pressure p and axial compressive force

    F at its ends. In order to produce pure shear state of stress in the

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    wall of the cylinder, F should be equal to

    (A) p r2 (B) p r2 2

    (C) p r3 2 (D) p r4 2

    Question. 29

    Consider the beam AB shown in the figure below. Part AC of the

    beam is rigid while Part CB has the flexural rigidity EI. Identify the

    correct combination of deflection at end B and bending moment at

    end A, respectively

    (A) ,EI

    PL PL3

    23

    (B) ,EI

    PL PL3

    3

    (C) ,2EIPL

    PL38 3

    (D) ,EIPL

    PL38 3

    Question. 30

    A simply supported beam AB has the bending moment diagram as

    shown in the following figure.

    The beam is possibly under the action of following loads

    (A) Couples ofM at C and 2M at D

    (B) Couples of 2M at C and M at D

    (C) Concentrated loads of /M L at C and 2 /M L at D

    (D) Concentrated load of /M L at C and couple of 2M at D

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    Question. 31

    A beam with the cross-section given is subjected to a positive bending

    moment (causing compression at the top) of 16 kNm acting around

    the horizontal axis. The tensile force acting on the hatched area ofthe cross-section is

    (A) zero (B) 5.9 kN

    (C) 8.9 kN (D) 17.8 kN

    Question. 32

    If a beam of rectangular cross-section is subjected to a vertical shear

    force V, the shear force carried by the upper one-third of the cross-

    section is

    (A) zero (B) V277

    (C) V278

    (D) V3

    Question. 33

    For the section shown below, second moment of the area about an

    axis /d 4 distance above the bottom of the area is

    (A) bd48

    3

    (B) bd12

    3

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    (C) bd48

    7 3 (D) bd

    3

    3

    Question. 34

    I-section of a beam is formed by gluing wooden planks as shown in

    the figure below. If this beam transmits a constant vertical shear

    force of 3000 N, the glue at any of the four joint will be subjected to

    a shear force (in kN per meter length) of

    (A) 3.0 (B) 4.0

    (C) 8.0 (D) 10.7

    Common data for questions 35 & 36 :

    Consider a propped cantilever beam ABC under two leads of

    magnitude P each as shown in the figure below. Flexural rigidity of

    the beam is EI.

    Question. 35

    The reaction at C is

    (A) ( )L

    Pa169 upwards (B) ( )

    LPa

    169 downwards

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    (C) ( )L

    Pa89 upwards (D) ( )

    LPa89 downwards

    Question. 36

    The rotation at B is

    (A) ( )EI

    PLa165 clockwise (B) ( )

    EIPLa

    165 anticlockwise

    (C) ( )EI

    PLa1659 clockwise (D) ( )

    EIPLa

    1659 anticlockwise

    YEAR 2005 ONE MARK

    Question. 37

    The symmetry of stress tensor at a point in the body under equilibrium

    is obtained from

    (A) conserved of mass

    (B) force equilibrium equations

    (C) moment equilibrium equations

    (D) conservation of energy

    Question. 38

    The components of strain tensor at a point in the plane strain case can

    be obtained by measuring longitudinal strain in following directions

    (A) along any two arbitrary directions

    (B) along any three arbitrary directions

    (C) along two mutually orthogonal directions

    (D) along any arbitrary direction

    YEAR 2005 TWO MARK

    Question. 39

    If principal stresses in a two-dimensional case are 10 MPa and 20

    MPa respectively, then maximum shear stress at the point is

    (A) 10 MPa (B) 15 MPa

    (C) 20 MPa (D) 30 MPa

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    Question. 40

    The bending moment diagram for a beam is given below :

    The shear force at sections aal and bbl respectively are of the

    magnitude

    (A) 100 kN, 150 kN (B) zero, 100 kN

    (C) zero, 50 kN (D) 100 kN, 100 kN

    Question. 41

    A circular shaft shown in the figure is subjected to torsion T at two

    point A and B. The torsional rigidity of portions CA and BD is GJ1

    and that of portion AB is GJ2. The rotations of shaft at points A and

    B are 1 and 2 . The rotation 1 is

    (A)GJ GJ

    TL1 2+

    (B)GJTL

    1

    (C) GJTL

    2 (D) GJ GJ TL1 2

    YEAR 2004 ONE MARK

    Question. 42

    For linear elastic systems, the type of displacement function for the

    strain energy is

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    (A) linear (B) quadratic

    (C) cubic (D) quartic

    YEAR 2004 TWO MARK

    Question. 43

    In a two dimensional stress analysis, the state of stress at a point

    is shown below. If 120 MPa = and 70 MPa = , andx y , are

    respectively,

    (A) 26.7 MPa and 172.5 MPa (B) 54 MPa and 128 MPa

    (C) 67.5 MPa and 213.3 MPa (D) 16 MPa and 138 MPa

    Question. 44

    For the linear elastic beam shown in the figure, the flexural rigidity,

    EI is 781250 kNm2. When 10w kN/m= , the vertical reaction RA at

    A is 50 kN. The value ofRA for 100w kN/m= is

    (A) 500 kN (B) 425 kN

    (C) 250 kN (D) 75 kN

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    Question. 45

    A homogeneous, simply supported prismatic beam of width B, depth

    D and span L is subjected to a concentrated load of magnitude P

    . The load can be placed anywhere along the span of the beam. Themaximum flexural stress developed in beam is

    (A)BDPL

    32

    2 (B) BDPL

    43

    2

    (C)BDPL

    34

    2 (D) BDPL

    23

    2

    Question. 46

    A circular solid shaft of span 5L m= is fixed at one end and freeat other end. A twisting moment 100T kNm= is applied at the free

    end. The torsional rigidity GH is 50000 kNm /rad2 .

    Following statements are made for this shaft :

    1. The maximum rotation is 0.01 rad

    2. The torsional strain energy is 1 kNm

    With reference to the above statements, which of the following applies

    ?

    (A) Both statements are true

    (B) Statement 2 is true but 2 is false

    (C) Statement 2 is true but 1 is false

    (D) Both the statements are false

    Common Data for Question 47 & 48 :

    A three-span continuous beam has an internal hinge at B. Section B

    is at the mid-span of AC. Section E is at the mid-span of CG. The

    20 kN load is applied at section B whereas 10 kN loads are applied

    at sections D and F as shown in the figure. Span GH is subjected

    to uniformly distributed load of magnitude 5 kN/m. For the loading

    shown, shear force immediate to the right of section E is 9.84 kN

    upwards and the hogging moment at section E is 10.31 kNm

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    Question. 47

    The magnitude of the shear force immediate to the left and immediate

    to the right of section B are respectively

    (A) 0 and 20 kN (B) 10 kN and 10 kN

    (C) 20 kN and 0 (D) 9.84 kN and 10.16 kN

    Question. 48

    The vertical reaction at support H is

    (A) 15 kN upward (B) 9.84 kN upward

    (C) 15 kN downward (D) 9.84 kN downward

    YEAR 2003 ONE MARK

    Question. 49

    A bar of varying square cross-section is loaded symmetrically as

    shown in the figure. Loads shown are placed on one of the axes of

    symmetry of cross-section. Ignoring self weight, the maximum tensile

    stress in N/mm2 anywhere is

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    (A) 16.0 (B) 20.0

    (C) 25.0 (D) 30.0

    Question. 50

    A curved member with a straight vertical leg is carrying a vertical

    load at Z, as shown in the figure. The stress resultants in the XY

    segment are

    (A) bending moment, shear force and axial force

    (B) bending moment and axial force only

    (C) bending moment and shear force only

    (D) axial force only

    YEAR 2003 TWO MARK

    Question. 51

    The state of two dimensional stresses acting on a concrete lamina

    consists of a direct tensile stress, 1.5 N/mmx2 = , and shear stress,

    1.20 N/mm2 = , which cause cracking of concrete. Then the tensile

    strength of the concrete in N/mm2 is

    (A) 1.50 (B) 2.08

    (C) 2.17 (D) 2.29

    Question. 52

    A " "H shaped frame of uniform flexural rigidity EI is located as

    shown in the figure. The relative outward displacement between

    points K and O is

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    (A)EI

    RLh2 (B)

    EIRL h2

    (C)

    EI

    RLh

    3

    2

    (D)

    EI

    RL h

    3

    2

    Question. 53

    A simply supported beam of uniform rectangular cross-section of

    width b and depth h is subjected to linear temperature gradient 0c at

    the top and Tc at the bottom, as shown in the figure. The coefficient

    of linear expansion of the beam material is . The resulting vertical

    deflection at the mid-span of the beam is

    (A)L

    Th8

    upward2

    (B)h

    TL8

    upward2

    (C)L

    Th8

    downward2

    (D)h

    TL8

    downward2

    Question. 54

    List I shows different loads acting on a beam and List II shows

    different bending moment distributions. Match the load with the

    corresponding bending moment diagram.

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    Codes :

    A B C D

    (A) 4 2 1 3

    (B) 5 4 1 3

    (C) 2 5 3 1

    (D) 2 4 1 3

    Question. 55

    A long structural column (length L= ) with both ends hinged is actedupon by an axial compressive load, P. The differential equation

    governing the bending of column is given by :

    EIdx

    d y2

    2

    Py=

    Where y is the structural lateral deflection and EI is the flexural

    rigidity. The first critical load on column responsible for its buckling

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    is given by

    (A)LEI2

    2 (B)

    LEI2

    2

    2

    (C) LEI2 22

    (D) LEI4 22

    **********