Quiznetik

Engineering Physics | Set 4

1. For an aluminium the modulus of rigidity is 2.1×1010 N/m2 and density is 2.7×103 kg/m3. Find the speed of transverse waves in the medium.

Correct : B. 2.79×103 m/s

2. Sound travels through a gas under which of the following condition?

Correct : C. adiabatic condition

3. What kind of wave is formed in organ pipes?

Correct : D. longitudinal stationary waves

4. A wave transmits momentum. Can’t it transfer angular momentum?

Correct : B. no

5. What is the most fundamental property of wave?

Correct : C. frequency

6. Which of the following is also known as pressure waves?

Correct : B. longitudinal waves

7. In which medium sound travels faster?

Correct : A. solid

8. TEM and SEM are the same microscopy techniques.

Correct : A. true

9. The resolving power of TEM is derived from

Correct : A. electrons

10. The cathode of transmission electron microscope consists of a

Correct : A. tungsten wire

11. The resolution attainable with standard TEM is less than the theoretical value.

Correct : A. true

12. During TEM, a vacuum is created inside the

Correct : C. column

13. Which of the following component of TEM focuses the beam of electrons on the sample?

Correct : B. condenser lens

14. Image formation in electron microscope is based on

Correct : C. differential scattering

15. The biological materials have little intrinsic capability to

Correct : A. scatter electrons

16. Glutaraldehyde is a

Correct : B. fixative

17. Osmium is a

Correct : B. heavy metal

18. Shadow casting is a technique of visualizing

Correct : A. isolated particles

19. Which of the following can be a wave function?

Correct : B. sin x

20. Which of the following is not a characteristic of wave function?

Correct : D. physically significant

21. dΨ/dx must be zero.

Correct : B. false

22. Any wave function can be written as a linear combination of

Correct : C. eigen functions

23. The Schrödinger is a differential equation.

Correct : B. false

24. The walls of a particle in a box are supposed to be

Correct : D. infinitely hard and infinitely large

25. The wave function of the particle lies in which region?

Correct : C. 0 < x < l

26. The particle loses energy when it collides with the wall.

Correct : B. false

27. The Energy of the particle is proportional to

Correct : C. n2

28. For a particle inside a box, the potential is maximum at x =

Correct : A. l

29. The Eigen value of a particle in a box is

Correct : D. √2/l

30. Particle in a box can never be at rest.

Correct : A. true

31. The wave function for which quantum state is shown in the figure?

Correct : B. 2

32. The line at which the tunnel wall breaks from sloping outward can be given as

Correct : A. spring line

33. Which of the following should be considered while aligning a tunnel?

Correct : B. hydrological conditions

34. Among the following, which doesn’t belong to tunnel classification?

Correct : C. rocky ground

35. Which method can be adopted if full face excavation is not possible?

Correct : D. benching

36. Among the following, which can be adopted for providing support for soft strata?

Correct : C. bents of steel

37. A steel cylinder which is pushed in the soft soil is determined as

Correct : B. shield

38. Which method can be adopted in case of rock tunneling?

Correct : A. full face method

39. Which of the following can act as an alternative for blasting?

Correct : D. fire-setting

40. Which of the following involves in the sequence of rocky strata?

Correct : A. marking profile

41. Which of the following are true for electron microscopy?

Correct : D. specimen should be thin and dry, image is obtained on a phosphorescent screen and electron beam must pass through evacuated chamber

42. Negative Staining is used for examining

Correct : D. virus particles, protein molecules and bacterial flagella

43. Which among the following helps us in getting a three-dimensional picture of the specimen?

Correct : B. scanning electron microscope

44. The secondary electrons radiated back in scanning microscope is collected by?

Correct : B. anode

45. On what factors do the intensity of secondary electrons depend upon?

Correct : D. size and chemical composition of the irradiated object, number of electrons ejected and on the number of electrons reabsorbed by surrounding

46. Where do we obtain the magnified image of the specimen in SEM?

Correct : A. cathode ray tube

47. Which of the following techniques are used in Transmission Electron Microscopy (TEM) for examining cellular structure?

Correct : D. negative-staining, shadow casting, ultrathin sectioning, freeze-etching

48. Which of the following properties is generally exhibited by amorphous solids?

Correct : B. glass-transition

49. Metal glass was first prepared at:

Correct : A. california institute of technology

50. Polycrystalline solids are isotropic.

Correct : A. true

51. Metal glasses differ from their crystalline counterparts in many ways. Chief application(s) of metal glasses include(s):

Correct : B. power transformers

52. Soda-lime glass is the most common type of glass. The component present in largest w/w percentage is:

Correct : A. sio2

53. Lead-oxide glass is called “crystal glass” because:

Correct : D. none of the mentioned

54. Crystallinity increases with increasing rate of cooling of a liquid.

Correct : B. false

55. 2 SINGLE CRYSTALS: UNIT CELL, CRYSTAL SYSTEMS, BRAVAIS LATTICES, DIRECTIONS AND PLANES IN A CRYSTAL, MILLER INDICES

Correct : A. unit cell edge lengths

56. In cubic crystals, crystallographic directions are arranged in families. Which of the following directions does not belong to the family <110>?

Correct : D. none of the mentioned view answer

57. Which of the following is a property of Miller indices?

Correct : C. they are not fractions

58. Miller indices for perpendicular planes are always the same.

Correct : B. false view answer

59. For destructive interference to take place, the path difference between the two waves should be:

Correct : A.

60. Bragg’s law is not a sufficient condition for diffraction by crystalline solids.

Correct : A. true

61. The Miller indices h, k, and l of parallel planes in a BCC lattice should satisfy which of the following X-ray diffraction reflection rules?

Correct : A. h + k + l should be even

62. Laue’s model pictures XRD as reflection from parallel crystalline planes. Reflection is different from refraction as:

Correct : D. all of the mentioned view answer

63. K-alpha x-rays have shorter wavelengths than K-beta x-rays?

Correct : B. false view answer

64. Which of the following has a HCP crystal structure?

Correct : D. zr

65. Amorphous solids have                structure.

Correct : C. irregular

66. At                  iron changes its BCC structure to FCC.

Correct : D. 906oc

67. At room temperature, tin is formed into

Correct : B. white tin

68. Which of the following is a property of non-metallic crystals?

Correct : C. low electrical conductivity

69. Which of the following is not an amorphous material?

Correct : C. lead

70. The smallest portion of the lattice is known as

Correct : D. unit cell

71. A unit cell that contains lattice points only at the corners is known as

Correct : A. primitive unit cell

72. The axial relationship of a monoclinic crystal system is given as

Correct : D. a ≠ b ≠ c

73. The axial relationship of a rhombohedral crystal system is given as

Correct : A. a = b = c

74. The interracial angles of a hexagonal crystal system are given by

Correct : B. α = β = 90o ϒ = 120o

75. The interracial angles of a triclinic crystal system are given by

Correct : D. α ≠ β ≠ ϒ ≠ 90o

76. What is the atomic radius of a BCC crystal structure?

Correct : D. a√3/4

77. What is the coordination number of a simple cubic structure?

Correct : A. 6

78. What is the atomic packing factor of BCC structure?

Correct : B. 0.68

79. Which of the following is a point defect in crystals?

Correct : B. interstitialcies

80. The defect that occurs due to a displacement of an ion is known as

Correct : C. frankel defect

81. Which defect does the following figure depict?

Correct : B. schottky defect

82. Which defect does the following diagram represent?

Correct : D. interstitial defect

83. occurs when a foreign substance replaces an atom in a crystal.

Correct : B. substitutional impurity

84. A disturbance in a region between two ideal parts of a crystal is known as

Correct : C. line defect

85. In screw dislocation, the Burger’s vector lies                    to the dislocation line.

Correct : B. parallel

86. Generation of dislocations can be identified using

Correct : D. frank-read mechanism

87. What are one-dimensional defects?

Correct : C. line defect

88. What are two-dimensional defects?

Correct : A. boundary defect

89. How is the dislocation energy defined?

Correct : A. j m-1

90. Which one of the following, is a line imperfection?

Correct : C. dislocation

91. What is the range of dislocation density in pure and unhardened metals?

Correct : A. 1010 – 1012 m-2

92. What is unit of dislocation density?

Correct : B. m-2

93. 6 BURGER VECTORS, STACKING FAULTS - ROLE OF

Correct : C. increase or decrease in strength depending on dislocation density

94. The number of dislocations increases drastically during

Correct : B. plastic deformation

95. Positive edge dislocation is denoted by

Correct : C.

96. Edge dislocation introduces shear strain only.

Correct : B. false

97. What term is used for the defect, produced by an array of dislocations that produces a small difference in orientation between the adjoining lattices?

Correct : D. low angle grain boundary

98. Which statement is false?

Correct : A. plastic deformation decreases dislocation density.

99. Most crystalline materials have dislocations in their as formed state.

Correct : A. true

100. Dislocation density can vary from

Correct : A. 105 – 1012 cm-2