Quiznetik

Engineering Materials | Set 3

1. X-rays cannot penetrate through

Correct : D. Lead

2. In Brinell hardness testing the time of loading is

Correct : C. 15 seconds

3. The property of material by which it can be rolled into sheets is called

Correct : D. Malleability

4. Which is amorphous material out of the following?

Correct : E. Glass

5. The greatest amount of strain energy per unit volume that a material can absorb sithout exceeding its elastic limit is

Correct : D. Toughness

6. The fatigue limit of a shaft connot be increased by

Correct : D. Surface decarburisation

7. A composite bar of steel and copper is heated. The copper bar will be under

Correct : A. compression

8. Hot hardness of high speed steels increases due to the addition of

Correct : A. Tungsten

9. Coal used in a cupola is

Correct : E. Coke

10. In cold working of metals

Correct : B. Strength and hardness of steel is increased

11. Number of isotopes for iron is

Correct : C. 4

12. A ductile fracture is usually not preceded by

Correct : C. noise

13. In high speed steel the maximum percentage of any alloying element is

Correct : C. Tungsten

14. Cemented carbide tools are generally not used for the machining of

Correct : D. Brass

15. The structure of common glass is

Correct : A. Amorphous

16. The purpose of annealing is to

Correct : D. Remove stresses

17. The behaviour of visco-elastic materials is

Correct : A. time dependent

18. What is the atomic or ionic characteristic that determines the elements of which the atom or iron is representative?

Correct : D. The number of protons

19. Which of the following increases when copper is hard drawn into wires?

Correct : C. Resistivity

20. The number of elastic constants for a completely anisotropie elastic material which follows Hooke's law is

Correct : B. 21

21. Which of the following materials have maximum magnetic permeability?

Correct : E. Gram oriented Si-Fe

22. Monel metal is

Correct : E. Chromium - Molybdenum alloy

23. Copper sheets are manufactured by

Correct : E. Rolling

24. If steel is quenched in water, the structure obtained is

Correct : A. Martensite

25. Brinell and Vickers hardness values are practically identical upto a hardness of

Correct : A. 300

26. If a material has similar properties throughout its volume, it is said to be

Correct : A. Homogeneous

27. Which of the following material can withstand maximum shocks without failure?

Correct : A. Malleable cast iron

28. Heavy water is obtained by

Correct : E. Prolonged electrolysis of water

29. Identify the incorrect statement

Correct : D. As the roughness of surface increses the fatigue life of speoimen increases

30. Pipes for bicycle frames are made of

Correct : A. Cold rolled steel

31. When a Ge-crystal is doped with phosphorous atom, it becomes

Correct : B. N-type semi-conductor

32. The graphite rods in a nuclear pile

Correct : E. Convert fast moving neutrons into thermal neutrons

33. Bakelite is

Correct : B. uncombustible

34. The material which undergo recoverable deformation and exhibit rubber like elsticity are called

Correct : B. Elastomers

35. Cold worked components are generally subjected to

Correct : A. Annealing

36. Figure of merit is used to

Correct : A. compare the efficiency of chermoelectric materials

37. An elastic behaviour of materials is expressed in terms of

Correct : B. Adiabatic time

38. Metal spinning

Correct : A. Is done on symmetrical articles

39. Trimming is a process associated with

Correct : E. Forging

40. The property by which a body returns to its original shape after the removal to the load is called

Correct : C. Elasticity

41. The phenomenon of weld decay is found in

Correct : E. Stainless steel

42. Which of the following is the major constituent of corundum?

Correct : E. Al2O3

43. Which of the following material has highest specific gravity?

Correct : D. Lead

44. The number of semi-conductors in periodic table is

Correct : D. 13

45. The operation of cutting out flat areas to some desired shape and which is generally the first step in a series of operations is known as

Correct : E. Blanking

46. The material for wire drawing should have

Correct : E. High ductility

47. Which one of the following is usually most ductile?

Correct : C. Face centred cubic lattic

48. The maximum hardenability of any steel depends on

Correct : A. The carbon content

49. In case of biaxial stress system when a member is subjected to tensile stresses in two perpendicular directions the maximum shear stress in case of mild steel occurs on a plane inclined at

Correct : E. 45?

50. Steel may be manufactured by

Correct : B. Open hearth process

51. Electro-forming is particularly vauable for

Correct : E. Thin walled parts requiring a high order of accuracy and internal surface finish

52. Wrought iron is

Correct : B. Easily hardened

53. Which one is different from the remaining

Correct : B. Electroplating

54. All of the following are examples of ceramic materials EXCEPT

Correct : A. Bakelite

55. Process of making a thin phosphate coating on steel to act as a base or primer for enamels and paints in known as

Correct : E. Parkerizing

56. A thermocouple works on which of the following effect?

Correct : B. Seeback effect

57. The highest percentage of carbon that an iron carbon alloy can have is

Correct : E. 6.60%

58. A lead based bearing alloy contains

Correct : D. Lead-antimony-tin-copper

59. The solid solution carbon in alpha iron obtained on cooling of 0.2% carbon steel which have been heated above the third critical point is called

Correct : D. Ferrite

60. Corrosion resistance of steels is increased by the addition of alloying elements like

Correct : C. Cobalt and vanadium

61. Galena is the ore for

Correct : B. Lead

62. Plastic deformation which is carried out in a temperature region and over a time interval such that the strain hardening is not relieved is known as

Correct : B. Cold work

63. Within elastic limits

Correct : C. Deformation is proportional to the load

64. The ability of material to absorb energy when deformed elastically and to return it when unloaded is called

Correct : A. Resilience

65. The variable stress below which the probability of failure of a material is negligible, is called

Correct : B. Tolerance limit

66. In a glass metal seal the two components must match with respect to their

Correct : E. Thermal expansion

67. The phenomenon of materials in which slow extension of materials takes place with the time at constant load is known as

Correct : D. Creep

68. Tensile strength of common varieties of cast iron is in the range

Correct : E. 140 - 500 M Pa

69. Which of the following material has least coefficient of expansion?

Correct : E. Invar

70. Iron alloyed with carbon more than 2% is called

Correct : C. Cast iron

71. A surface damage which results when two surfaces in contact experience light periodic relative motion is

Correct : A. Fretting

72. During induction hardening the depth of hardening is controlled by

Correct : B. Voltage

73. Stress concentration may be caused by

Correct : B. A home or a notch in the body

74. Polystrene at room temperature is

Correct : A. Brittle

75. Small end of a connecting rod forging is

Correct : C. Broached

76. If steel is slowly cooled in furnace, the structure obtained is

Correct : A. Pearlite

77. Machinability of a metal depends on

Correct : D. (A) and (B) above

78. Which is expected to be strongest in tension?

Correct : C. Piano wire

79. When metal is deformed by cold work, severe stresses known as residual stresses are undesirable and to remove them

Correct : C. The metal should be reheated below recrystallization temperature

80. The ability of a tool to resist softening at high temperatures is known as

Correct : B. Red hardness

81. Which of the following is a mesomorphous material?

Correct : C. Mica

82. Electron with energy level of 2 MeV is considered as

Correct : A. Fast electron

83. Shot peening

Correct : D. Improves fatigue life of small parts

84. when atoms are hold together by the sharing of valence electrons

Correct : A. They form a covalent bond

85. When piece of 0.2% carbon steel is heated above third critical point the steel is a solid solution of carbon in gamma iron and called

Correct : B. Austenite

86. The common household glass is

Correct : D. Soda lime glass

87. Silicon doped with phosphorous is an

Correct : D. n-type semi-conductor

88. When a normal atom loses an electron, the atom

Correct : A. Becomes a positive ion

89. Steel pipes are generally manufactured by

Correct : C. Extrusion process

90. Which of the following class of materials are good conductors of heat and electricity?

Correct : E. Metals

91. The ability of a material to absorb energy in the plastic range is known as

Correct : C. Toughness

92. Sorbite' is obtained when

Correct : B. Steel is annealed

93. Selenium is an

Correct : A. intrinsic semi-conductor

94. In ferromagnetic materials

Correct : B. the atomic magnetic moments are parallel

95. Machining properties of steel are improved by adding

Correct : B. Lead

96. In compression, a prism of brittle material will break

Correct : C. By shearing slong oblique plane

97. Monel metal consists of

Correct : B. Aluminium copper and nickel

98. Cadmium sulphide cell is a

Correct : A. Photo conductive cell

99. Which process is different from the others

Correct : A. Drop forging

100. By alloying copper with manganese which of the following increases?

Correct : B. Tensile strength