# Interference and Diffraction MCQs Quiz Multiple Choice Questions & Answers Page 2

## Interference and Diffraction Questions with Answers

51. Newtons light illustrate the phenomenon of

52. Newtons rings are formed because of interference between the light Reflected from

53. Newtons rings experiment is performed and radius (or diameter) is calculated. Now Plano-convex lens is replaced with another Plano-convex lens of greater Radius of curvature. What will be effect on radius (or diameter)?

54. Newtons rings experiment is performed with air gap between lens and plate. Now that gap is filled with water. What will be effect on radius (or diameter)?

55. On a rainy day, small oil films on water show brilliant colors. This is due to

56. Optical fiber works on the

57. Radio telescopes are better than optical telescopes because

58. Rainbow is due to

59. Second glass plate in Michelson s Interferometer is known as

60. significant diffraction of X ray can be obtained

61. The angle of incidence for a wave

62. The characteristic that distinguishes a laser beam from an ordinary light beam is

63. The conditions for the production of constructive and destructive interference are reversed due to the fact that on striking the thin film

64. The critical angle for a beam of light passing from water into air is 48.8 degree. This means that all light rays with an angle of incidence greater than this angle will be

65. The dark lines constituting the absorption spectrum exhibited by sunlight are frequently called

66. The diffraction observed by diffraction grating can also be termed as

67. The first reflecting telescope was built by

68. The grating used to observe, diffraction of visible light can have approximately

69. The interference in thin films is because

70. The number of lines on plane gratings is 5000. If it is illuminated by a wavelength of light 6000 Ao, how many orders will be visible?

71. The phenomenon of diffraction can be understood using

72. The phenomenon of Newtons rings can be used to check the

73. The points of constructive interference of light are

74. The principle on which fiber optics is based is

75. The Radius (or diameter) of bright rings in Newtons rings is

76. The Radius (or diameter) of dark rings in Newtons rings is

77. The region of the electromagnetic spectrum immediately above the frequencies to which the human eye is sensitive is called

78. The speed of any mechanical wave as it propagates through a medium is dependent mainly on the

79. The speed of light in material A is 1.25 times as large as it is in material. What is the ratio of the refractive indices, ÂµA /ÂµB of these materials?

80. The wave nature of light is demonstrated by which of the following?

81. There are two types of diffraction Fresnel and ..........

82. To find prominent diffraction, the size of diffraction object should be

83. Two sources of light are said to be coherent if

84. What is the effect of increasing the number of slits on the intensity of Central maxima of diffraction pattern of a diffraction grating?

85. What is the highest order spectrum which may be seen with monochromatic light of wavelength 5000 Ao by means of diffraction grating with 5000 lines/cm?

86. What is the name of the process whereby waves travel around corners and obstacles in their paths?

87. What is the nature of interference pattern at the contact edge of wedge shaped film

88. What is the nature of interference pattern for thin film of wedge shaped

89. What is the nature of interference pattern for thin film of wedge shaped

90. What is the speed of light in glycerin (n = 1.47) expressed in terms of the speed of light in a vacuum?

91. What is true for intensity of scattered light according to Rayleighs law?

92. When a light ray travelling in glass is incident on an air surface

93. When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to

94. When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to

95. When electromagnetic waves strike the boundary of denser medium they are

96. When light passes from air into water, the frequency of the light remains the same. What happens to the speed? And the wavelength of light as it crosses the boundary in going from air into water? Speed Wavelength

97. When Newtons rings interference pattern is viewed from above by means of reflected light, the central spot is

98. Which of the following condition is essential for observing Fraunhofer diffraction?

99. Which of the following does not support the wave nature of light

100. Which of the following does NOT travel in a vacuum?