Strength of Materials (Practice Test)1. 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(e) none of the above.

2. Hooke's law holds good upto(a) yield point(b) limit of proportionality(c) breaking point(d) elastic limit(e) plastic limit.

3. 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(e) longitudinal stress and lateral strain.

4. The unit of Young's modulus is(a) mm/mm(b) kg/cm(c) kg(d) kg/cm2(e) kg cm2.

5. Deformation per unit length in the direction of force is known as(a) strain(b) lateral strain(c) linear strain(d) linear stress(e) unit strain.

6. It equal and opposite forces applied to a body tend to elongate it, the stress soproduced is called(a) internal resistance(b) tensile stress(c) transverse stress(d) compressive stress(e) working stress.

7. The materials having same elastic properties in all directions are called(a) ideal materials(b) uniform materials(c) isotropic materials(d) practical materials(e) elastic materials.

8. A thin mild steel wire is loaded by adding loads in equal increments till it breaks. Theextensions noted with increasing loads will behave as under(a) uniform throughout(b) increase uniformly(c) first increase and then decrease(d) increase uniformly first and then in-crease rapidly(e) increase rapidly first and then uniformly.

9. 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(e) linear stress and lateral strain.

10. 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) become one-fourth(e) remain unaffected.

Answers:

1. d2. b3. c4. d5. c6. b7. c8. d9. d10. ePrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLinks to this postLabels:Mechanical - Strength of MaterialsSaturday, February 2, 2013Strength of Materials (Stresses in Beams)Q.1. Which of the following statements regarding assumptions in analysis of stressed beam is false(a) The material is homogeneous and isotropic, so that it has the same elastic properties in all directions(b) Modules of elasticity in tension and compression are equal(c) The radius of curvature of the beam before bending is equal to that of its transverse dimensions(d) Normal sections of the beam, which were plane before bending, remain plane after bending

Q.2. A steel flat 10 cm wide and 2 cm thick is bent into a circular arc of 50 metres radius. The maximum intensity of stress induced will be(E = 2.05 x 105 N/mm2)(a) 31 N/mm2(b) 41 N/mm2(c) 51 N/mm2(d) 61 N/mm2

Q.3. A strip of steel 1 mm thick is bent into an arc of a circle of 1 m radius. The maximum bending stress will be(E = 200 Gnm-2)(a) 25 MPa(b) 50 MPa(c) 64 MPa(d) 100 MPa

Q.4. An steel wire of 20 mm diameter is bent into a circular shape of 10 m radius. If E, the modulus of elasticity is 2 x 106 kg/cm2, then the maximum stress induced in the wire is(a) 103kg/cm2(b) 2 x 103 kg/cm2(c) 4 x 103 kg/cm2(d) 6 x 103(IES 1995)

Q.5. A high strength steel band saw of 90 mm width and 0.5 mm thickness runs over a pulley of 500 mm diameter. Assuming E = 200 Gpa, the maximum flexural stress developed would be(a) 100 MPa(b) 200 MPa(c) 400 MPa(d) 500 MPa (IES 1998)

Q.6. A mild steel fleet of width 120 mm and thickness 10 mm is bent into an arc of a circle of radius 10 m by applying a pure moment M. If E is 2 x 105N/mm2, then the magnitude of the pure moment M will be(a) 2 x 106N-mm(b) 2 x 105N-mm(c) 0.2 x 105N-mm(d) 0.2 x 104N-mm (IES 1999)

Q.7. A steel cantilever beam 5 m in length is subjected to a concentrated load of 1 kN acting at the free end of the bar. The beam is of rectangular cross section, 50 mm wide by 75 mm deep. The stress induced in the beam will be(a) 0(b) 107 MPa(c) 110 MPa(d) 117 MPa

Q.8. A beam of circular cross section is 200 mm in diameter. It is simply supported at each end and loaded by two concentrated loads of 100 kN, applied 250 mm from the ends of the beam. The maximum stress in the beam will be(a) 63.6 MPa(b) 31.8 MPa(c) 17.6 MPa(d) 0

Q.9. A beam is loaded by a couple of 1 kNm at each of its ends. The beam is steel and of rectangular cross section 25 mm wide by 50 mm deep. The maximum bending stress will be(a) 24 MPa(b) 48 MPa(c) 72 MPa(d) 96 MPa

Q.10. A beam 3 m in length is simply supported at each end and bears a uniformly distributed load of 10 kN per metre of length. The cross section of the bar is rectangular, 75 mm x 150 mm. Maximum bending stress in the beam will be(a) 20 MPa(b) 40 MPa(c) 60 MPa(d) 80 MPa

Answers:1-c 2-b 3-d 4-b 5-b 6-b 7-b 8-b 9-d 10-bPrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsSaturday, January 12, 2013Strength of Materials (Torsion of Shafts)

Q.1. A propeller shaft in a ship is 350 mm in diameter. the allowable working stress in shear is 50 MPa and the allowable angle of twist is 1 degree in 15 diameters of length. If G = 85 GNm-2, then the shaft can transmit a maximum torque of(a) 350 kNm(b) 378 kNm(c) 416 kNm(d) 545 kNm

Q.2. In the above problem if a 175 mm axial hole is bored through the length of shaft and if other conditions remain same then torsional load carrying capacity of the shaft will be reduced by(a) 1%(b) 3%(c) 6%(d) 9%

Q.3. In the above problem, by what percentage is the weight of the shaft reduced?(a) 25%(b) 50%(c) 75%(d) 53.6%

Q.4. If the driving torque is applied at one end and the resting torque at the other end then the shafts are said to be joined in(a) series(b) parallel(c) a combination of series and parallel(d) none of these

Q.5. If two shafts are joined in series then(a) resulting shaft is called compound(composite) shaft(b) both shafts carry the same torque(T)(c) total angle of twist at the fixed or resisting end() is the sum of separate angles of twist of the two shafts(d) all of the above

Q.6. The shafts are said to be joined in parallel if(a) torque(T) is applied at the junction of the two shafts(b) resisting torques T1 and T2 are applied at their ends(c) both (a) and (b)(d) neither (a) nor (b)

Q.7. If two shafts are connected in parallel then(a) resulting shaft is called composite(or compound) shaft(b) angle of twist in each shaft will be equal(c) both (a) and (b)(d) neither (a) nor (b)

Q.8. A compound shaft is composed of a 500 mm length of solid copper 100 mm in diameter, joined to a 1 m length of solid steel 125 mm in diameter. A torque of 15 kNm is applied to each end of the shaft. The maximum shear stress in copper will be(G for copper = 40 GNm-2and G for steel is 85 GNm-2)(a) 76 MPa(b) 39 MPa(c) 47 MPa(d) 88MPa

Q.9. In the above problem, maximum shearing stress in steel will be(a) 76 MPa(b) 39 MPa(c) 47 MPa(d) 88 MPa

Q.10. In the above problem, total angle of twist of the entire shaft will be(a) 0.016 rad(b) 0.026 rad(c) 0.046 rad(d) 0.5 rad

Answers1. c 2. c 3. a 4. a 5. d 6. c 7. c 8. a 9. b 10. bPrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsThursday, January 3, 2013Strength of Materials (Torsion of Shafts)Q.1. Two steel shafts A and B are used for transmitting power. The ratio of revolutions of shafts i.e. NA/NB= 2. The ratio of torques on shafts i.e. TA/TB= 1/2. The ratio of the horse power transmitted by the shafts i.e. PA/PBare(a) 1/2(b) 1/4(c) 1(d) 2

Q.2. A twisting moment of 1 kNm is impressed upon a 50 mm diameter shaft, then maximum shear stress will be(a) 25 MPa(b) 32 MPa(c) 37 MPa(d) 41 MPa

Q.3. In above problem, what is the angle of twist in a 1 m length of the shaft if G = 85 GNm-2?(a) 0.011 radian(b) 0.019 rad(c) 0.1 radian(d) 0.0001 radian

Q.4. There are two shafts of equal length. One shaft is solid having diameter d and another shaft is hollow with inner diameter equal to 3/4 of outer diameter(D). If both shafts are required to transmit a given torsional load then weight of hollow shaft will be ___ % of solid shaft.(a) 25.7%(b) 50%(c) 56.3%(d) 75%

Q.5. A hollow steel shaft 3 m long must transmit a torque of 25 kNm. The total angle of twist in this length is not to exceed 2.50 and the allowable shearing stress is 90 MPa. The inside diameter of the shaft will be(a) 100 mm(b) 125 mm(c) 145 mm(d) 165 mm

Q.6. In the above problem, the outside diameter of the shaft will be(a) 145 mm(b) 165 mm(c) 175 mm(d) 200 mm

Q.7. An axial core of 100 mm is bored throughout the length of a 200 mm diameter solid circular shaft. For the same maximum shear stress, the percentage torque carrying capacity lost by this operation is(a) 6.25(b) 12.5(c) 25(d) 45 (AMIE Winter 1998)

Q.8. A composite shaft is fabricated from a 50 mm diameter solid aluminium alloy, G = 30 GNm-2, surrounded by a hollow steel circular shaft of outside diameter 65 mm and inside diameter 50 mm, G = 85 GNm-2. This composite shaft is loaded by a twisting moment of 1.5 kNm, the shearing stress at the outer fibres of the steel will be(a) 18 MPa(b) 24 MPa(c) 30 MPa(d) 36 MPa

Q.9. In the above problem, the shearing stress at the outer fibres of aluminium will be(a) 1 MPa(b) 2.8 MPa(c) 5.6 MPa(d) 9.8 MPa

Q.10. A hollow shaft has outer diameter 125 mm and inner diameter 75 mm. Shearing stress at the inside fibres is 50 MPa. The shearing stress at the outer fibre will be(a) 74.7 MPa(b) 55 MPa(c) 81.7 MPa(d) 83.3 MPa

Answers1. c 2. d 3. d 4. c 5. b 6. a 7. a 8. d 9. d 10. dPrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsMonday, December 31, 2012Engineering Mechanics Questions and Answers from GATE and IES ExamsClick herefor PDF file.PrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsThursday, September 6, 2012Strength of Materials (Torsion of Shafts)Q.1. For a solid or a hollow shaft subject to a twisting moment T, the torsional shearing stressat a distance r from the centre will be (a)= Tr/J (b)= Tr (c)= TJ/r (d) none of these where J is second moment of area.

Q.2. A hollow prismatic beam of circular section is subjected to a torsional moment. The maximum shear stress occurs at (a) inner wall of cross section (b) middle of thickness (c) outer surface of shaft (d) none of these(AMIE Winter 1997)

Q.3. A solid shaft has diameter 80 mm. It is subjected to a torque of 4 KNm. The maximum shear stress induced in the shaft would be (a) 75/N/mm2 (b) 250/N/mm2 (c) 125/N/mm2 (d) 150/N/mm2(IES 2001)

Q.4. If in a bar after twisting moment T has been applied, a line on surface is moved by an anglethen shearing moment will be (a)/ (b) (c)/ (d) none of these

Q.5. Shear modulus G is given by (a)G =/ (b) G =/ (c) G = T/ (d) G = T/

Q.6. A shaft of length L is subject to a constant twisting moment T along its length L, then anglethrough which one end of the bar will twist relative to other will be (a) T/ (b) T/GJ (c) GJ/TL (d) TL/GJ

Q.7. A circular shaft subjected to torsion undergoes a twist of 10in a length of 120 cm. If the maximum shear stress induced is limited to 1000 kg/cm2and if modulus of rigidity G = 0.8 x 106then the radius of the shaft should be (a)/8 (b)/27 (c) 18/ (d) 27/(IES 1993) Hint:/r = G/l

Q.8. At fully plastic twisting moment (a) only fibres at surface are stressed to yield point in shear (b) fibres at centre are stressed to yield point in shear (c) all fibres are stressed to yield point in shear (d) none of these

Q.9. The relationship among twisting moment(T) acting on a rotating shaft, power in watt(W), and angular velocity in radian per second() will be (a) T = W/ (b) W = T (c) W = T/ (d) none of these

Q.10. A shaft turns at 150 rpm under a torque of 1500 N-m. Power transmitted is (a) 15kW (b) 10kW (c) 7.5kW (d) 5kW (IES 1999) Hint: P = 2NT/60

Answers:1. a2. c3. c4. b5. a6. d7. d8. c9. b10. c

PrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsThursday, August 23, 2012Strength of Materials (Stresses and Strains)Q.1. If all the dimensions of a prismatic bar of square cross section suspended freely from the ceiling of a roof are doubled then the total elongation produced by its own weight will increase(a) eight times(b) four times(c) three times(d) two times (IES 1996)Q.2. For an isotropic material, the number of independent material constants are(a) 1(b) 2(c) 3(d) 4 (AMIE Winter 1999)

Q.3. In an experiment it is found that the bulk modulus of a material is equal to its shear modulus. The Poissons ratio is(a) 0.125(b) 0.250(c) 0.375(d) 0.500 (IES 1998)

Q.4. A given material has Youngs modulus E, modulus of rigidity G and Poissons ratio 0.25. The ratio of Youngs modulus to modulus of rigidity of the material is(a) 3.75(b) 3(c) 2.5(d) 1.5 (IES 1997)

Q.5. The bulk modulus of elasticity of a material is twice its modulus of rigidity. The Poissons ratio of the material is(a) 1/7(b) 2/7(c) 3/7(d) 4/7 (IES 2002)

Q.6. A cylindrical bar of 20 mm diameter and 1 m length is subjected to a tensile test. Its longitudinal strain is 4 times that of its lateral strain. If the modulus of elasticity is2 x 105N/mm2, then its modulus of rigidity is(a) 8 x 106N/mm2(b) 8 x 105N/mm2(c) 0.8 x 104N/mm2(d) 0.8 x 105N/mm2 (IES 1999)

Q.7. What would be the height to which a vertical concrete wall may be built given an ultimate compressive strength of 16 MPa and a safety factor of 4? The weight density of concrete is20 kNm-3.(a) 50 m(b) 100 m(c) 150 m(d) 200 m

Q.8. A bar of uniform cross section is subject to uniaxial tension and develops a strain in the direction of the force of 1/800. Assuming= 1/3, the change of volume per unit volume will be(a) 1/1000(b) 1/1200(c) 1/2400(d) 1/4800

Q.9. A bar 4 cm in diameter is subjected to an axial load of 4 t. The extension of the bar over a gauge length of 20 cm is 0.03 cm. The decreases in diameter is 0.0018 cm. The Poissons ratio is(a) 0.25(b) 0.30(c) 0.33(d) 0.35 (IES 1994)

Q.10.A bar 30 mm in diameter was subjected to tensile load of 54 kN and the measured extension on 300 mm gauge length was 0.112 mm and change in diameter was 0.00366 mm. Poissons ration will be(a) 0.25(b) 0.326(c) 0.356(d) 0.28

Answer:1. b2. d3. a4. c5. b6. d7. d8. c9. b10. bPrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsWednesday, August 22, 2012Strength of Materials (Stresses & Strains)Q.1. The work done on a unit volume of material, as simple tensile force is gradually increased from zero to a value causing rupture, is called(a) modulus of elasticity(b) modulus of toughness(c) modulus of resilience(d) none of these

Q.2. The unit of modulus of resilience is(a) N-m^-2(b) Nm-m^-3(c) N-m^-3(d) none of these

Q.3. For most metals, Poissons ratio() lies in the range(a) 0.1 to 0.9(b) 0.05 to 0.1(c) 1 to 10(d) 0.25 to 0.35

Q.4. If a material contains same elastic properties in all directions at any point of the body then it is called(a) anisotropic(b) orthotropic(c) isotropic(d) none of these

Q.5. The stress level below which a material has a high probability of not failure under reversal of stress, is known as(a) elastic limit(b) endurance limit(c) proportional limit(d) tolerance limit (IES 1995)

Q.6. In fatigue of metals, the endurance limit is(a) less than yield stress(b) more than yield stress(c) equal to ultimate stress in a static test(d) none of these (AMIE Winter 1996)

Q.7. A steel cable of 2 cm diameter is used to lift a load of 500 kg. Given that, E = 2 x 106 kg/cm2 and the length of the cable is 10 m. Elongation of the cable due to the load will be(a) 0.5 cm(b) 0.25 cm(c) 1 cm(d) 2/ cm (IES 1993)Q.8. A mild steel bar is in two parts having equal lengths. The area of cross section of Part I is double that of Part II. If the bar carries an axial load P, then the ratio of elongation in Part I to that in Part II will be(a) 2(b) 4(c) 1/2(d) 1/4

Q.9. A bar of circular cross section varies uniformly from a cross section 2D to D. If extension of the bar is calculated treating it as a bar of average diameter, then the percentage error will be(a) 10(b) 25(c) 33.33(d) 50 (IES 1996)

Q.10.A bar of length L and constant cross section(A) is hanging vertically. What would be total increase in length due to self weight(W)?(a) WL/AE(b) 2WL/AE(c) WL/2AE(d) none of these

Answers:1. b2. b3. d4. c5. b6. c7. b8. c9. a10. cPrintPDFEmail ThisBlogThis!Share to TwitterShare to FacebookShare to PinterestLabels:Mechanical - Strength of MaterialsFriday, August 10, 2012Strength of Materials Quiz (Stresses and Strains)Q.1. A material having identical properties in all directions, is called(a) elastic(b) homogeneous(c) isotropic(d) all the above

Q.2. Match List I with List II and select the correct answer using the codes given below the lists: List IA. TenacityB. PlasticityC. DuctilityD. MalleabilityList II1. Continues to deform without much increase of stress2. Ultimate strength in tension3. Extension in a direction without rupture4. Ability to be drawn out by tension to a small section without ruptureCodes:(a) A2, B1, C4, D3(b) A2, B1, C3, D4(c) A1, B2, C4, D3(d) A1, B2, C3, D4 (IES 2000)

Q.3. Match list I(properties) with list II(stress points labelled 1, 2, 3, and 4) in the stress-strain figure and select the correct answer using the codes given below the lists: List IA. Yield pointB. Proportional limitC. Rupture strengthD. Ultimate strengthList IIFigureCodes:(a) A3, B4, C1, D2(b) A4, B3, C1, D2(c) A3, B4, C2, D1(d) A4, B3, C2, D1 (IES 2001)

Q.4. The ratio of unit stress to unit strain is called(a) modulus of elasticity(b) Youngs modulus(c) both (a) and (b)(d) neither (a) nor (b)

Q.5. The region in the stress-strain curve extending from origin to proportional limit is called(a) plastic range(b) elastic range(c) semi plastic range(d) semi elastic range

Q.6. In a stress strain curve there is a point at which there is increase in strain with no increase in stress. This point is called(a) point of failure(b) point of rupture(c) yield point(d) none of these

Q.7. The work done on a unit volume of material, as simple tensile force is gradually increased from zero to such a value that the proportional limit of the material is reached, is called(a) modulus of elasticity(b) modulus of toughness(c) modulus of resilience(d) none of these

Q.8. A 2 m long bar of uniform section extends 2 mm under limiting axial stress of 200 N/mm2. What is the modulus of resilience for the bar?(a) 0.10 units(b) 0.20 units(c) 10,000 units(d) 20,000 units (IES 1995) Hint: Modulus of res. = f2/2E

Q.9. The maximum energy stored at elastic limit of a material is called(a) resilience(b) proof resilience(c) modulus of resilience(d) bulk resilience (IES 1993)

Q.10. The work done on a unit volume of material, as simple tensile force is gradually increased from zero to a value causing rupture, is called(a) modulus of elasticity(b) modulus of toughness(c) modulus of resilience(d) none of these

Answers:1. c2. d3. a4. c5. b6. c7. c8. a9. b10. B1. When a body is subjected to transverse vibration, the stress included in a body will bea. Shear stress b. Bending stressc. Tensile stress d. None of the above2. Hooks law holds good up toa. Yield point b. Elastic limitc. Plastic limit d. None of the above3. The change in length due to tensile or compressive force acting on a body is given bya. PlA/E b. Pl/AE c. E/PlA d. None of the above4. Materials which are usually most ductilea. Face centred cubic lattice b. Body centred cubic latticec. Hexagonal closed packed lattice d. None of the above5. When a body is subjected to three mutually perpendicular stress of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known asa. Youngs modulus b. Bulk modulusc. Modulus of rigidity d. None of the above6. The extremities of any diameter on Mohrs circle represent.a. Principal stress b. Normal stress on plane at 45 degreec. Shear stress on plane 45 degree d. None of the above7. A body is subjected to a tensile stress of 60 MPa on a plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress isa. 400 MPa b. 500 MPa c. 1400 MPa d. None of the above8. A body is subjected to a two normal 20 MPa (tensile) and 10 MPa (compressive) acting perpendicular to each other. The maximum shear stress isa. 5 MPa b. 10 MPa c. 15 MPa d. None of the above9. Youngs modulus is a ratio ofa. Strain/Stress b. Change in length/Original lengthc. Stress/Strain d. Stress/Original length10. The ratio of lateral strain to the linear strain isa. Bulk modulus b. Youngs modulusc. Poissons ratio d. Modulus of rigidity11. A simply supported beam of length l is subjected to a symmetrical uniformly varying load with zero intensity at the ends and intensity w (load per unit length) at the mid span. What is the maximum bending moment?a. 3wl2/8 b. wl2/12 c. wl2/24 d. 5wl2/1212. Which one of the following is represented by the area of the S.F. diagram from one end upto a given location on the beam?a. B.M. at the location b. Load at the locationc. Slope at the location d. Deflection at the location13. For which of the following columns, Euler buckling load = 42EI/l2?a. Column with both hinged ends b. Column with one end fixed and other end freec. Column with both ends fixed d. Column with one end fixed and other hinged14. A horizontal beam under bending has a maximum bending stress of 100 MPa and a maximum shear stress of 20 MPa. What is the maximum principal stress in the beam?a. 20 b. 50 c. 50+2900 d. 10015. A closed coil helical springs has 15 coils. If five coils of this spring are removed by cutting, the stiffness of the modified spring willa. increases to 2.5 times b. increases to 1.5 timesc. reduce to 0.66 times d. remain unaffected16. Consider the following statement for a simply supported beam subjected to a couple at its mid span.1. Bending moment is zero at the ends and maximum at the centre2. Bending moment is constant over the entire length of the beam3. Shear force is constant over the entire length of the beam4. Shear force is zero over the entire length of the beamWhich of the following statements given above are correct?a. 1, 3 and 4 b. 2, 3 and 4 c. 1 and 3 d. 2 and 417. Two shafts having the same length and material are joined in series. If the ratio of the diameter of the first shaft to that of the second shaft is 2, then the ratio of the angle of twist of the first shaft to that of the second shaft isa. 16 b. 8 c. 4 d. 218. Which one of the following pairs is not correctly matched?(a) Slenderness ratio: The ratio of length of the column to the least radius of gyration(b) Buckling factor: The ratio of maximum load to the permissible axial load on the column(c) Short column: A column for which slenderness ratio 32(d) Strut: A member of a structure in any position and carrying an axial compressive load.19. The volumetric strain of a thin cylindrical shell with flat ends and subjected to internal pressure is the sum ofa. Longitudinal and hoop stress b. Longitudinal and diametrical strainc. hoop stress and twice the longitudinal strain d. Longitudinal strain and twice the hoop strain20. On a plane, resultant stress is inclined at an angle of 45 to the plane. If the normal stress is 100N/mm2, the shear stress on the plane isa. 71.5 N/mm2 b. 100 N/mm2 c. 86.6 N/mm2 d. 120.8 N/mm221. For which one of the following columns, Euler buckling load = (42EI)/l2?a. Column with both ends hinged b. Column with one end fixed and other end freec. Column with both ends fixed d. Column with one end fixed and other hinged.22. A horizontal beam under bending has a maximum bending stress of 100 MPa and a maximum shear stress of 20 MPa. What is the maximum principal stress in the beam?a. 20 b. 50 c. 50 + 2900 d. 10023. A closed coil helical spring has 15 coils. If five coils of this spring are removed by cutting, the stiffness of the modified spring willa. increases to 2.5 times b. increase to 1.5 timesc. reduce to 0.66 times d. remain unaffected24. For 1 2and 3= 0, what is the physical boundary for Rankine failure theory?a. A rectangle b. An ellipse c. A square d. A parabola25. The volumetric strain of a thin cylindrical shell with flat ends and subjected to internal pressure is the sum ofa. Longitudinal and hoop strain b. Longitudinal and diametrical strainc. hoop strain and twice the longitudinal strain d. longitudinal strain and twice the hoop strain26. A simply supported beam of span l is subjected to a uniformly varying load having zero intensity at the left support and w N/m at the right support. The reaction at the right support isa. wl/2 b. wl/5 c. wl/4 d. wl/327. A cast iron specimen in a torsion test gives aa. cup and cone fracture b. fracture along a plane normal to the axis of the specimenc. fracture along a helix of approximately 45 d. fracture along a plane inclined at 60 to the axis28. A shaft is subjected to a bending moment M=400 N.m. and Torque T=300 N.m. The equivalent bending moment isa. 900 N.m b. 700 N.m c. 500 N.m d. 450 N.m29. The percentage change in volume of a thin cylinder under internal pressure having hoop stress = 200 MPa, E = 200 GPa and Poissons ratio = 0.25 isa. 0.40 b. 0.30 c. 0.25 d. 0.2030. If the numbers of turns in a spring are halved, its stiffness isa. halved b. doubled c. increased four times d. not changed

1.The intensity of stress which causes unit strain is called

unit stress

bulk modulus

modulus of rigidity

modulus of elasticity

principal stress.

2.The Young's modulus of a wire is defined as the stress which will increase the length of wire compared to its original length

half

same amount

double

one-fourth

four times.

3.Percentage reduction of area in performing tensile test on cast iron may be of the order of

50%

25%

0%

15%

60%.

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

doubled

halved

become four times

become one-fourth

remain unaffected.

5.During a tensile test on a specimen of 1 cm cross-section, maximum load observed was 8 tonnes and area of cross-section at neck was 0.5 cm2. Ultimate tensile strength of specimen is

4 tonnes/cm2

8 tonnes/cm2

16 tonnes/cm2

22 tonnes/cm2

none of the above.

6.True stress-strain curve for materials is plotted between

load/original cross-sectional area and change in length/original length

load/instantaneous cross-sectional area original area and log.

load/instantaneous cross-sectional area and change in length/original length

load/instantaneous area and instantaneous area/original area

none of the above.

7.Which is the false statement about true stress-strain method

It does not exist

It is more sensitive to changes in both metallurgical and mechanical conditions

It gives, a more accurate picture of the ductility

It can be correlated with stress-strain values in other tests like torsion, impact, combined stress tests etc.

It can be used for compression tests as well.

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

internal resistance

tensile stress

transverse stress

compressive stress

working stress.

9.In a tensile test on mild steel specimen, the breaking stress as compared to ultimate tensile stress is

more

less

same

more/less depending on composition

may have any value.

10.Modulus of rigidity is defined as the ratio of

longitudinal stress and longitudinal strain

volumetric stress and volumetric strain

lateral stress and lateral strain

shear stress and shear strain

linear stress and lateral strain.

11.The value of modulus of elasticity for mild steel is of the order of

2.1xl05 kg/cm2

2.1 X 106 kg/cm2

2.1 x 107 kg/cm2

0.1 xlO6 kg/cm2 (

opt 5

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

strain

lateral strain

linear strain

linear stress

unit strain.

13.A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under

uniform throughout

increase uniformly

first increase and then decrease

increase uniformly first and then in-crease rapidly

increase rapidly first and then uniformly.

14.The unit of Young's modulus is

mm/mm

kg/cm

kg

kg/cm2

kg cm2.

15.Which of the following materials is most elastic

rubber

plastic

brass

steel

glass.

16.If a part is constrained to move and heated, it will develop

principal stress

tensile stress

compressive stress

shear stress

no stress.

17.The ultimate tensile stress of mild steel compared to ultimate compressive stress is

same

more

less

more or less depending on other factors

unpredictable.

18.Hooke's law holds good upto

yield point

limit of proportionality

breaking point

elastic limit

plastic limit.

19.Young's modulus is defined as the ratio of

volumetric stress and volumetric strain

lateral stress and lateral strain

longitudinal stress and longitudinal strain

shear stress to shear strain

longitudinal stress and lateral strain.

20.The impact strength of a material is an index of its

toughness

tensile strength

capability of being cold worked

hardness

fatigue strength.

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

area at the time of fracture

original cross-sectional area

average of (a) and (b)

minimum area after fracture

none of the above.

22.Which of the following has no unit

kinematic viscosity

surface tension

bulk modulus

strain

elasticity.

23.For steel, the ultimate strength in shear as compared to in tension is nearly

same

half

one-third

two-third

one-fourth.

24.The materials having same elastic properties in all directions are called

ideal materials

uniform materials

isotropic materials

practical materials

elastic materials.

1.The ratio of lateral strain to the linear strain within elastic limit is known as

Young's modulus

bulk modulus

modulus of rigidity

modulus of elasticity

Poisson's ratio.

2.Poisson's ratio is defined as the ratio of

longitudinal stress and longitudinal strain

longitudinal stress and lateral stress

lateral stress and longitudinal stress

lateral stress and lateral strain

none of the above.

3.The value of Poisson's ratio for cast iron is

0.1 to 0.2

0.23 to 0.27

0.25 to 0.33

0.4 to 0.6

3 to 4.

4.The property of a material which allows it to be drawn into a smaller section is called

plasticity

ductility

elasticity

malleability

durability.

5.The change in the unit volume of a material under tension with increase in its Poisson's ratio will ,

increase

decrease

remain same

increase initially and then decrease

unpredictable.

6.The total elongation produced in a bar of uniform section hanging vertically downwards due to its own weight is equal to that produced by a weight

of same magnitude as that of bar and applied at the lower end

half the weight of bar applied at lower end

half of the square of weight of bar applied at lower end

one-fourth of weight of bar applied at lower end

none of the above.

7.The stress developed in a material at breaking point in extension is called

breaking stress

fracture stress

yield point stress

ultimate tensile stress

proof stress.

8.In the tensile test, the phenomenon of slow extension of the material, i. e. stress increasing with the time at a constant load is called

creeping

yielding

breaking

plasticity

none of the above.

9.If a material expands freely due to heating it will develop

thermal stresses

tensile stress

bending

compressive stress

no stress.

10.Flow stress corresponds to

fluids in motion

breaking point

plastic deformation of solids

rupture stress

none of the above.

11.The property of a material by virtue of which a body returns to its original, shape after removal of the load is called

plasticity

elasticity

ductility

malleability

resilience.

12.The property of a material by virtue of which it can be beaten or rolled into plates is called

malleability

ductility

plasticity

elasticity

reliability.

13.The buckling load for a given material depends on

slenderness ratio and area of cross-section

Poisson's ratio and modulus of elasticity

slenderness ratio and modulus of elasticity

slenderness ratio, area of cross-section and modulus of elasticity

Poisson's ratio and slenderness ratio.

14.Rupture stress is

breaking stress

maximum load/original cross-sectional area 04)

load at breaking point/A

load at breaking point/neck area

maximum stress.

15.The materials which exhibit the same elastic properties in all directions are called

homogeneous

inelastic

isotropic

isotropic

relativistic.

16.The ratio of direct stress to volumetric strain in case of a body subjected to three mutually perpendicular stresses of equal intensity, is equal to

Young's modulus

bulk modulus

modulus of rigidity

modulus of elasticity

Poisson's ratio.

17.For which material the Poisson's ratio is more than unity

steel

copper

aluminum

cast iron

none of the above.

18.The stress necessary to initiate yielding is

considerably greater than that necessary to continue it

considerably lesser than that necessary to continue it

greater than that necessary to stop it

lesser than that necessary to stop it

equal to that necessary to stop it.

19.In question 56, the internal reaction in bottom 80 cm length will be

same in both cases

zero in first case

different in both cases

data are not sufficient to determine same

none of the above.

20.The stress at which extension of the material takes place more quickly as compared to the increase in load is called

elastic point of the material

plastic point of the material

breaking point of the material

yielding point of the material

ultimate point of the material.

21.When it is indicated that a member is elastic, it means that when force is applied, it will

not deform

be safest

stretch

not stretch

none of the above.

22.The percentage reduction in area of a cast iron specimen during tensile test would be of the order of

more than 50%

2550%

1025%

510%

negligible.

23.The elasticity of various materials is controlled by its

ultimate tensile stress

proof stress

stress at yield point

stress at elastic limit

tensile stress.

24.In a tensile test, near the elastic limit zone, the

tensile strain increases more quickly

tensile strain decreases more quickly

tensile strain increases in proportion to the stress

tensile strain decreases in proportion to the stress

tensile strain remains constant.

1.The force acting along the circumference will cause stress in the walls in a direction normal to the longitudinal axis of cylinder; this stress is called

longitudinal stress

hoop stress

yeiled stress

ultimate stress

none of the above.

2.A riveted joint in which every rivet of a row is opposite to other rivet of the outer row, is known as

chain riveted joint

diamond riveted joint

cross-cross riveted joint

zig-zag riveted joint

none of the above.

3.Efficiency of a riveted joint is the ratio of its strength (max. load it can resist without failure) to the strength of the unpunished plate in

tension

compression

bearing

any one of the above

none of the above.

4.A cylindrical section having no joint is known as

joint less section

homogeneous section

perfect section

manufactured section

seamless section.

5.A riveted joint in which the number otrivets decrease from innermost to outer most row is called

chain riveted joint

diamond riveted joint

cross-cross riveted joint

zig-zag riveted joint

none of the above.

6.Proof resilience per material is known as

resilience

proof resilience

modulus of resilience

toughness

impact energy.

7.The distance between the centers of the rivets in adjacent rows of zig-zag riveted joint is known as

pitch

back pitch

diagonal pitch

diametral pitch

lap.

8.The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is

same

twice

four times

eight times

half.

9.A material capable of absorbing large amount of energy before fracture is known as

ductility

toughness

resilience

shock proof

plasticity.

10.A non-yielding support implies that the

support is frictionless

support can take any amount of reaction

support holds member firmly

slope of the beam at the support is zero

none of the above.

11.If the rivets in adjacent rows are staggered and the outermost row has only one rivet, the arrangement of the rivets is called

chain riveting

zig zag riveting

diamond riveting

cross-cross riveting

none of the above.

12.Diamond riveted joint can be adopted in the case of following type of joint

butt joint

lap joint

double riveted lap joints

all types of joints

none of the above.

13.Rivets are made of following type of material

tough

hard

resilient

ductile

malleable.

14.The stress induced in a body due to suddenly applied load compared to when it is applied gradually is

same

half

two times

four times

none of the above.

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

impact energy

resilience

proof resilience

modulus of resilience

toughness.

16.The ratio of elongation in a prismatic bar due to its own weight (W) as compared to another similar bar carrying an additional weight (W) will be

1:2

1 : 3

1 : 4

1 : 2.5

1 : 2.25.

17.The total strain energy stored in a body is termed as

resilience

proof resilience

modulus of resilience

toughness

impact energy.

18.In a prismatic member made of two materials so joined that they deform equally under axial stress, the unit stresses in two materials are

equal

proportional to their respective moduli of elasticity

inversely proportional to their moduli of elasticity

average of the sum of moduli of elasticity

none of the above.

19.A boiler shell 200 cm diameter and plate thickness 1.5 cm is subjected to internal pressure of 1.5 MN/m , then the hoop stress will be

30 MN/m2

50 MN/m2

100 MN/m2

200 MN/m2

300 MN/m2.

20.A beam is loaded as cantilever. If the load at the end is increased, the failure will occur

in the middle

at the tip below the load

at the support

anywhere

none of the above.

21.The deformation of a bar under its own weight compared to the deformation of same body subjected to a direct load equal to weight of the body is

same

double

half

four times

one-fourth.

22.Resilience of a material is considered when it is subjected to

frequent heat treatment

fatigue

creep

shock loading

resonant condition.

23.When two plates are butt together and riveted with cover plates with two rows of rivets, the joi;it is known as

lap point

butt joint

single riveted single cover butt joint

double riveted double cover butt joint

single riveted double cover butt joint.

24.The weakest section of a diamond riveting is the section which passes through

the first row

the second row

the central row

one rivet hole of the end row

none of the above.

25.In riveted boiler joints, all stresses, shearing, bearing and tensile are based on the

size of rivet

size of the drilled or reamed hole

average of size of rivet and hole

smaller of the two

any one of the above.

1.The safe twisting moment for a compound shaft is equal to the

maximum calculated value

minimum calculated value

mean value

extreme value

none of the above.

2.Shear stress induced in a shaft subjected to tension will be

maximum at periphery and zero at center

maximum at center

uniform throughout

average value in center

none of the above.

3.The torsional rigidity of a shaft is expressed by the

maximum torque it can transmit

number of cycles it undergoes before failure

elastic limit upto which it resists torsion, shear and bending stresses

torque required to produce a twist of one radian per unit length of shaft

maximum power it can transmit at highest possible-speed.

4.In a belt drive, the pulley diameter is doubled, the belt tension and pulley width remaining same. The changes required in key will be

increase key length

increase key depth

increase key width

double all the dimensions

none of the above.

5.A key is subjected to side pressure as well at shearing forces. These pressures are called

bearing stresses

fatigue stresses

crushing stresses

resultant stresses

none of the above.

6.The value of shear stress which is induced in the shaft due to the applied couple varies

from maximum at the centre to zero at the circumference

from zero at the centre to maximum at the circumference

from maximum at the centre to mini-mum at the cricumference

from minimum at the centre to maxi-mum at the circumference

none of the above.