Unit-I : Fundamental of Mechanical Engineering MCQ

1. The slope of the stress-strain curve in the elastic deformation region is ____

(A) Elastic modulus

(B) Plastic modulus

(C) Poisson’s ratio

(D) None of the mentioned

Answer: a

2. What is the stress-strain curve?

(A) It is the percentage of stress and stain

(B) It is the relationship between stress and strain

(C) It is the difference between stress and strain

(D) None of the mentioned

Answer: b

3. Which point on the stress strain curve occurs after the proportionality limit?

(A) Upper yield point

(B) Lower yield point

(C) Elastic limit

(D) Ultimate point

Answer: c

4. Which point on the stress strain curve occurs after the lower yield point?

(A) Yield plateau

(B) Upper yield point

(C) Ultimate point

(D) None of the mentioned

Answer: a

5. Which point on the stress strain curve occurs after yield plateau?

(A) lower yield point

(B) Upper yield point

(C) Ultimate point

(D) Breaking point

Answer: c

6. Which point on the stress strain curve occurs after the ultimate point?

(A) Last point

(B) Breaking point

(C) Elastic limit

(D) Material limit

Answer: b

7. Elastic limit is the point ____

(A) up to which stress is proportional to strain

(B) At which elongation takes place without application of additional load

(C) Up to which if the load is removed, original volume and shapes are regained

(D) None of the mentioned

Answer: c

8. What is the point P shown on the stress strain curve?

(A) Upper yield point

(B) Yield plateau

(C) Elastic limit

(D) Ultimate point

Answer: d

9. What is the point P shown in the stress-strain curve?

(A) Lower yield point

(B) Elastic limit

(C) Proportionality limit

(D) Breaking point

Answer: d

10. What is the point shown in the stress strain curve?

(A) Elastic limit

(B) Lower yield point

(C) Yield plateau

(D) Lower strain point

Answer: b

11. Where is the necking region?

(A) The area between lower yield point and upper yield point

(B) The area between the plastic limit and elastic limit

(C) The area between the ultimate point and initial point

(D) The area between the ultimate point and rupture

Answer: d

12. The dimension of strain is?

(A) LT-2

(B) N/m2

(C) N

(D) Dimensionless

Answer: d

13. What is tensile strain?

(A) The ratio of change in length to the original length

(B) The ratio of original length to the change in length

(C) The ratio of tensile force to the change in length

(D) The ratio of change in length to the tensile force applied

Answer: a

14. Find the strain of a brass rod of length 250mm which is subjected to a tensile load of 50kN when the extension of rod is equal to 0.3mm?

(A) 0.025

(B) 0.0012

(C) 0.0046

(D) 0.0014

Answer: b

15. Find the elongation of an steel rod of 100mm length when it is subjected to a tensile strain of 0.005?

(A) 0.2mm

(B) 0.3mm

(C) 0.5mm

(D) 0.1mm

Answer: c

16. i) Strain is a fundamental behaviour of a material.

ii) Strain does not have a unit.

(A) Both i and ii are true and ii is the correct explanation of i

(B) Both i and ii are true but ii is not the correct explanation of i

(C) i is true but ii is false

(D) ii is true but i is false

Answer: b

17. A tensile test was conducted on a steel bar. The gauge length of the bar was 10cm and the extension was 2mm. What will be the percentage elongation?

(A) 0.002

(B) 0.02

(C) 0.2

(D) 2

Answer: d

18. The lateral strain is _____

(A) The ratio of axial deformation to the original length

(B) The ratio of deformation in area to the original area

(C) The strain at right angles to the direction of applied load

(D) The ratio of length of body to the tensile force applied on it

Answer: c

19. Find the strain of a brass rod of length 100mm which is subjected to a tensile load of 50kN when the extension of rod is equal to 0.1mm?

(A) 0.01

(B) 0.001

(C) 0.05

(D) 0.005

Answer: b

20. The stress which acts in a direction perpendicular to the area is called ____

(A) Shear stress

(B) Normal stress

(C) Thermal stress

(D) None of the mentioned

Answer: b

21. Which of these are types of normal stresses?

(A) Tensile and compressive stresses

(B) Tensile and thermal stresses

(C) Shear and bending

(D) Compressive and plane stresses

Answer: a

22. In a body loaded under plane stress conditions, what is the number of independent stress components?

(A) 1

(B) 2

(C) 3

(D) 6

Answer: c

23. If a bar of large length when held vertically and subjected to a load at its lower end, its won-weight produces additional stress. The

maximum stress will be ____

(A) At the lower cross-section

(B) At the built-in upper cross-section

(C) At the central cross-section

(D) At every point of the bar

Answer: b

24. Which type of stress does in a reinforcement bar is taken by the concrete?

(A) Tensile stress

(B) Compressive stress

(C) Shear stress

(D) Bending stress

Answer: b

25. A material has a Poisson’s ratio of 0.5. If uniform pressure of 300GPa is applied to that material, What will be the volumetric strain of

it?

(A) 0.5

(B) 0.20

(C) 0.25

(D) Zero

Answer: d

26. A diagram which shows the variations of the axial load for all sections of the pan of a beam is called ____

(A) Bending moment diagram

(B) Shear force diagram

(C) Thrust diagram

(D) Stress diagram

Answer: d

27. The stress induced in a body, when subjected to two equal and opposite forces which are acting tangentially across the resisting section resulting the shearing of the body across its section is called ____

(A) Bending stress

(B) Compressive stress

(C) Shear strain

(D) Shear stress

Answer: d

28. What is the formula for shear stress?

(A) Shear resistance/shear area

(B) Force/unit area

(C) Bending strain/area

(D) Shear stress/length

Answer: a

29. The law which states that within elastic limits strain produced is proportional to the stress producing it is known as _____

(A) Bernoulli’s law

(B) Hooke’s law

(C) Stress law

(D) Poisson’s law

Answer: b

30. What is the factor of safety?

(A) The ratio of stress to strain

(B) The raio of permissible stress to the ultimate stress

(C) The ratio of ultimate stress to the permissible stress

(D) The ratio of longitudinal strain to stress

Answer: c

31. What is Hooke’s law for the 1-D system?

(A) The relation between normal stress and the corresponding strain

(B) The relation between shear stress and the corresponding strain

(C) The relation between lateral strain and the corresponding stress

(D) None of the mentioned

Answer: a

32. Limit of proportionality depends upon ____

(A) Area of cross-section

(B) Type of loading

(C) Type of material

(D) All of the mentioned

Answer: a

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

(A) Elastic point

(B) Plastic point

(C) Breaking point

(D) Yielding point

Answer: d

34. Which of these is a non-hoookean material?

(A) Steel

(B) Rubber

(C) Aluminium

(D) Copper

Answer: b

35. Where in the stress-strain curve, the hooke’s law is valid?

(A) Strain hardening region

(B) Necking region

(C) Elastic range

(D) Valid everywhere

Answer: c

36. Highest value of stress for which Hooke’s law is applicable for a given material is called

(A) Stress limit

(B) Strain limit

(C) Proportional limit

(D) Significant limit

Answer: c

37. The loading limit under which the deformation entirely disappears on removal of load is called——

(A) Elastic limit

(B) Proportionality limit

(C) Yield point

(D) Yong’s modulus

Answer: a

38. The slope of linearly elastic portion of stress strain diagram is a measure of—-

(A) Modulus of elasticity

(B) Modulus of rigidity

(C) Bulk modulus

(D) Elastic limit

Answer: a

39. If both the modulus of elasticity and shear modulus of a metal are doubled, the Poisson’s ratio of the metal will—-

(A) Double

(B) Half

(C) increase four times

(D) remain unaffected

Answer: d

40. Stress represents the —–

(A) external force acting on the body

(B) pressure setup within the body material

(C) force by which the material of the body opposes the deformation

(D) resistance per unit area to deformation by internal forces

Answer: d

41. Young’s modulus of elasticity for a perfectly rigid body is—

(A) zero

(B) unity

(C) infinity

(D) some finite non-zero value

Answer: c

42. For a given material, the modulus of rigidity is 100 GPa and the Poisson’s ratio is 0.25. the value of modulus of elasticity in GPa is—

(A) 12.5

(B) 150

(C) 200

(D) 250

Answer: d

43. A steel bar of 1.5 m length, 50 mm wide and 20 mm thick is subjected to an axial tensile load of 120 kN. If the extension in length of

bar is 0.9 mm, the modulus of elasticity of bar material is—

(A) 50 KPa

(B) 100 KPa

(C) 150 KPa

(D) 200 KPa

Answer: d

44. A simply supported beam of length 4m and carrying a point load of 15N at mid span will have a maximum bending moment of—

(A) 10 N-m

(B) 15 N-m

(C) 20 N-m

(D) 25 N-m

Answer: b

45. If a simply supported beam carries a UDL on entire length, the shear force—

(A) has a maximum value at the mid-point

(B) has a linear variation along entire length

(C) is constant at all sections

(D) is not zero at any section of the beam

Answer: b

46. A cantilever beam of length 3m is carrying a point load of 10 kN at its free end and a UDL of 12 kN/m over its entire span. The value of

moment acting at fixed end of the beam is—

(A) 80 KN-m

(B) 82 KN-m

(C) 84 KN-m

(D) 86 KN-m

Answer: c

47. In stress-strain graph which of the following is taken along x-axis?

(A) stress

(B) strain

(C) force

(D) Young’s modulus

Answer: b

48. In stress-strain curve, the point occurring after elastic limit is

(A) Proportionality limit

(B) ultimate point

(C) yield point

(D) breaking point

Answer: c

49. Which of the following are statically determine beams?

(A) only simply supported beams

(B) Cantilever, simply supported and overhanging beams

(C) Fixed beams

(D) Continuous beams

Answer: b

50. What is the distance of point of contra-flexure from point A in the beam loaded as shown in following figure—

(A) 1m

(B) 0.5m

(C) 0.2m

(D) 0.3m

Answer: c

51. The value of reaction at point B in following beam is—

(A) 21N

(B) 22N

(C) 23N

(D) 24N

Answer: d

52. A force of 1000 KN is applied on a metallic bar of 10 cm diameter and 50 cm length. The change in diameter is observed as 0.25 mm. if

factor of safety of 2.5 is considered; the value of ultimate stress for the material in MPa is—

(A) 218

(B) 318

(C) 418

(D) 518

Answer: b

53. A rectangular bar of length 2m and crosssectional area 30cmX15cm is subjected to axial tensile force of 500 kN. If the Poisson’sratio and Bulk modulus of the bar material are 0.25 and 110 GPa respectively, the change in length of the bar will be–

(A) 0.013 mm

(B) 0.13 mm

(C) 1.3 mm

(D) 13mm

Answer: b

54. Hook’s law holds good up to—

(A) elastic limit

(B) proportionality limit

(C) yield point

(D) breaking point

Answer: b

55. A block of weight 200 KN is suspended from a vertical copper wire of 20 mm diameter and 3 m length. What will be the decrease in

diameter of the wire if E= 1×106 bar and μ =0.25.

(A) 0.01 mm

(B) 0.02 mm

(C) 0.03mm

(D) 0.04 mm

Answer: c

56. The value of Poisson’s ratio depends upon

(A) nature of load, i.e. tensile or compressive

(B) magnitude of load

(C) material of test specimen

(D) cross-section and dimension of test piece

Answer: c

57. The value of stress of 1 N/cm2 in MPa will be- —

(A) 0.001

(B) 0.01

(C) 0.1

(D) 1

Answer: b

58. If a simply supported beam carries a UVL on the entire span, the bending moment—

(A) has a maximum value at the mid span

(B) has a parabolic variation along the span

(C) is constant along the beam

(D) is zero at the ends of beam

Answer: d

59. A simply supported beam is loaded as shown in the figure given below. The maximum shear force in the beam will be—

(A) Zero

(B) W

(C) 2W

(D) 4W

Answer: c

60. The distance of point of contra-flexure from point C in the following beam is—

(A) 1m

(B) 2m

(C) 2.5m

(D) 3m

Answer: c

61. The value of bending moment at the ends in a simply supported beam—

(A) is always zero

(B) is always zero if the beam is not subjected to a couple at the ends

(C) equal to the reaction at the ends

(D) Can’t be predicted

Answer: b

62. A simply supported beam is subjected to a couple at mid-point, the variation of shear force along the entire beam will be—

(A) constant

(B) linear

(C) parabolic

(D) cubic

Answer: a

63. The maximum value of bending moment in a simply supported beam of length 4 m subjected to a UDL of intensity 20 kN/m over entire span will be—

(A) 40 KN-m

(B) 50 KN-m

(C) 60 KN-m

(D) 70 KN-m

Answer: a

64. The maximum value of shear force in a simply supported beam of length 3 m subjected to a UVL of maximum intensity 20 kN/m, as

shown in figure over entire span—

(A) 10 KN

(B) 20 KN

(C) 30 KN

(D) 40 KN

Answer: b

65. A cantilever beam is carrying several point loads. The shear force is maximum at—

(A) free end

(B) fixed end

(C) at the point of largest load

(D) mid point of beam

Answer: b

66. A cantilever beam of length 2 m is carrying a UDL of 10kN/m over half of its length starting from free end, the value of maximum bending moment is—

(A) 10 KN-m

(B) 15 KN-m

(C) 20 KN-m

(D) 25 KN-m

Answer: b