11th Class Physics Chapter 09 MCQs with Answers

Welcome to the 11th Class Physics Chapter 09 MCQs Online Test. We are presenting you with top MCQ questions from the 11th Class Physics Chapter Physical Optics.

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11th Class Physics Chapter 09 MCQs with Answers

The 11th Class Physics Chapter “Physical Optics” explores the fascinating field of optics, which deals with the behavior and properties of light. This chapter focuses on understanding the principles of physical optics, including the nature of light, the phenomenon of interference, and the formation of diffraction patterns.

The chapter begins by introducing the nature of light as an electromagnetic wave. Students will learn about the dual nature of light, which exhibits both wave-like and particle-like properties. They will understand the concepts of wavelength, frequency, and the speed of light, as well as the electromagnetic spectrum and the different regions within it.

Students will delve into the principles of interference, which is the interaction of two or more light waves. They will learn about the conditions for constructive and destructive interference, and how interference can result in the formation of bright and dark fringes. Students will explore interference in various contexts, such as thin films, double-slit experiments, and the Michelson interferometer.

The chapter further explores the phenomenon of diffraction, which occurs when light waves encounter an obstacle or aperture. Students will learn about the conditions for diffraction, and how it leads to the bending and spreading of light waves. They will understand the concept of diffraction patterns, including the single-slit diffraction pattern and the double-slit diffraction pattern.

Moreover, students will study the principles of polarization, which describes the orientation of light waves. They will learn about the polarization of light and the different types of polarizers. Students will understand the concepts of unpolarized light, polarized light, and the phenomenon of Malus’ law.

The chapter may also cover topics such as optical instruments, including lenses and mirrors, and their applications in forming images. Students will explore the principles of refraction, reflection, and the formation of images by lenses and mirrors.

To enhance understanding, the chapter may include practical examples, diagrams, and problem-solving exercises. Students will develop skills in analyzing and calculating quantities related to physical optics, applying the principles of interference and diffraction, and solving problems related to optics scenarios.

Studying “Physical Optics” in the 11th Class Physics curriculum provides students with a solid foundation in understanding the principles and applications of light and its interactions with matter. It prepares them for further studies in optics, photonics, and related fields. Additionally, it cultivates critical thinking skills, mathematical reasoning, and an appreciation for the role of light in our understanding of the physical world.

What is Physical Optics?

In physics, physical optics, or wave optics, is the branch of optics that studies interference, diffraction, polarization, and other phenomena for which the ray approximation of geometric optics is not valid.

Chapter 9 Physical Optics

1. The corpuscular nature of light was given by choosing which one is correct:

(a) Huygen

(b) Maxwell

(c) Newton

(d) Thomas young

2. Light is the source to choose which one is correct:

(a) Create energy

(b) Destroy energy

(c) Carry energy

(d) All of above

3. Wave theory of light was proposed by choose which one is correct:

(a) Thomas young

(b) Huygen

(c) Newton

(d) Maxwell

4. According to Newton, light travels in the form of choose which one is correct:

(a) Photons

(b) Waves

(c) Carpascular

(d) Electrons

5. Huygen proposed that light travels in spaced by means of wave motion in choose which one is correct:

(a) 1960

(b) 1690

(c) 1680

(d) 1670

6. Light is the type of choose which one is correct:

(a) Momentum

(b) Velocity

(c) Energy

(d) Acceleration

7. The light reaches the planet earth from the planet sun in plane choose which one is correct:

(a) Amplitude

(b) Frequency

(c) Wavelength

(d) Wavefronts

8. In interference and diffraction of light, the waves and wavefronts considered as choose which one is correct:

(a) Cylindrical

(b) Conical

(c) Spherical

(d) Plane

9. Huygen principle is used to explain the choose which one is correct:

(a) Dispersion of light

(b) Reflection of light

(c) Speed of light

(d) Propagation of light

10. The shape of wavefronts depends upon choose which one is correct:

(a) Shape of medium

(b) Viscosity of medium

(c) Density of medium

(d) All of above

11. The direction in which light energy is carried called choose which one is correct:

(a) Ray

(b) Wavefront

(c) Locus

(d) All of above

12. A plane wave is obtained if a point source of light is placed at the focus of a choose which one is correct:

(a) Glass

(b) Plane lens

(c) Mirror

(d) None of these

13. When the disturbance is propagated out in all directions from a point source, what will be the wavefronts choose which one is correct:

(a) Spherical

(b) Conical

(c) Plane

(d) None of these

14. All the points on a primary wavefront can be considered as the source for the production of secondary wavelets is choose which one is correct:

(a) Huygen principle

(b) Hertz principle

(c) Newton’s principle

(d) Maxwell’s principle

15. The electromagnetic theory was developed by choose which one is correct:

(a) Newton

(b) Huygen

(c) Maxwell

(d) Thomas young

16. Direction of propagation of light ray is choose which one is correct:

(a) Along the wavefront

(b) Perpendicular to wavefront

(c) At an angle of 45 0 to the plane of the wavefront

(d) None of these

17. Light waves are choose which one is correct:

(a) Complex

(b) Monochromatic

(c) Mixture of monochromatic and complex

(d) None of these

18. A medium which separates out a complex waves into component waves is called a choose which one is correct:

(a) Polarizing medium

(b) Refractive medium

(c) Dispersive medium

(d) None of these

19. When light waves pass through a dispersive medium what happens to them choose which one is correct:

(a) No effect at all

(b) Split into its component waves

(c) Both (a) and (b)

(d) None of these

20. When waves pass from one medium to another choose which one is correct:

(a) Their wavelength changes

(b) Their speed changes

(c) Frequency remains constant

(d) All of above

21. Electromagnetic theory of radiation failed to explain choose which one is correct:

(a) Compton effect

(b) Mass-energy relation

(c) Photoelectric effect

(d) All of them

22. Electromagnetic waves travel in free space with velocity equal to choose which one is correct:

(a) 3 x 1010 m/s

(b) 3 x 108 m/s

(c) 3 x 109 m/s

(d) 6 x 107 m/s

23. The first explanation of wave nature of light was provided in 1801 by the experiment of choose which one is correct:

(a) Maxwell

(b) Thomas young

(c) Huygen

(d) Newton

24. Huygen’s principle is used to explain choose which one is correct:

(a) The speed of light

(b) The polarisation

(c) Locate the wavefront

(d) None of these

25. The locus of all points in a medium having the same phase of vibration will be known as choose which one is correct:

(a) Wavefront

(b) Wavelength

(c) Focal length

(d) None of these

26. Huygen principle states that choose which one is correct:

(a) Light travel in electromagnetic waves

(b) Light has dual nature

(c) Light travel in straight line

(d) All points on primary wavefront are source of secondary wavelets

27. The phenomenon of the resultant wave obtained by overlapping of two or more waves is called choose which one is correct:

(a) Reflection

(b) Refraction

(c) Interference

(d) Polarisation

28. The monochromatic sources of light emit waves having a constant phase difference are called choose which one is correct:

(a) Reliable sources

(b) Unreliable sources

(c) Primary sources

(d) Coherent sources

29. Interference effects of light was verified by choose which one is correct:

(a) Bragg

(b) Newton

(c) Thomas young

(d) None of the above

30. Which one of the following is monochromatic light source choose which one is correct:

(a) Light from simple lamp

(b) Light from sodium lamp

(c) Light from fluouscent

(d) Light from neon lamp

31. Two sources of light are coherent if they emit rays of which among the following choose which one is correct:

(a) Same amplitude

(b) Same wavelengths

(c) Same amplitude and wavelength

(d) Same wavelength with constant phase coherence

32. When the crest of one wave falls on the crest of the other waves, this phenomena is known as choose which one is correct:

(a) Polarisation

(b) Dispersion

(c) Constructive interference

(d) Destructive interference

33. When crest of one wave falls over the trough of other wave, this phenomenon is known as choose which one is correct:

(a) Diffraction

(b) Polarisation

(c) Constructive interference

(d) Destructive interference

34. The blue of the sky is due to choose which one is correct:

(a) Diffraction

(b) Reflection

(c) Polarisation

(d) Scattering

35. In order to get interference of light waves choose which one is correct:

(a) The sources should be monochromatic

(b) The sources should be phase coherent

(c) The law of superposition should be applicable

(d) All of above

36. The condition for constructive interference of two waves is that the path difference should be choose which one is correct:

(a) Integral multiple of

(b) Integral multiple of

(c) Even integral multiple of

(d) None of these

37. The condition for destructive interference of two waves is that the path difference should be choose which one is correct:

(a) Integral multiple of

(b) Integral multiple of

(c) Odd integral multiple of

(d) None of these

38. In young’s double slit experiment, the path difference for bright fringe is choose which one is correct:

(a) d cos = m

(b) d sin m

(c) d sec = m

(d) d tan m

39. Indicate When one mirror of a Michelson interferometer is moved a distance of 0.5 mm, 2000 fringes ar observed, the wavelength of light used is choose which one is correct:

(a) 5000 nm

(b) 5000 Ao

(c) 500 cm

(d) 2000 Ao

40. The wavelength of X-rays is of the order of choose which one is correct:

(a) 10Ao

(b) 1000 Ao

(c) 1 Ao

(d) 100 Ao

41. Wavelength of X-rays falling at glancing angle of 300 on a crystal with atomic spacing 2 x 10-10 m for the first order diffraction is choose which one is correct:

(a) 4 x 1010 m

(b) 2 x 1010 m

(c) 0.2 x 1010 m

(d) 20x 1010 m

42. In young’s experiment if white light is used choose which one is correct:

(a) Dark fringe will be seen

(b) Bright fringe will be seen

(c) Alternate dark and bright fringes will be seen

(d) No fringe will be seen

43. What is the distance between any two consecutive bright fringes is known as choose which one is correct:

(a) Wavelet

(b) Fringe spacing

(c) Amplitude

(d) Wavelength

44. The interference fringe spacing depends upon choose which one is correct:

(a) Separation between the sources

(b) The wavelength of light used

(c) The distance of screen from the source

(d) All of above

45. A thin film is transparent medium whose thickness is comparable with wavelength of choose which one is correct:

(a) Sound

(b) Heat

(c) Light

(d) None of these

46. A thin layer of oil on the surface of water looks coloured due to choose which one is correct:

(a) Transmission of light

(b) Polarization of light

(c) Interference of light

(d) None of these

47. Soap film in sunlight appears coloured due to choose which one is correct:

(a) Diffraction of light

(b) Scattering of light

(c) Interference of light

(d) Dispersing of light

48. Brilliant and beautiful colours in soap bubbles on surface of water are due to choose which one is correct:

(a) Interference of heat

(b) Interference of light

(c) Interference of sound

(d) All of the above

49. A white light passed through a prism is choose which one is correct:

(a) Polarized

(b) Dispersed

(c) Diffracted

(d) Deviated

50. Newton’s rings are formed due to choose which one is correct:

(a) Reflection of light

(b) Polarization of light

(c) Interference of light

(d) Diffraction of light

51. When Newton’s rings interference is seen by mean of reflected light, the central spot is choose which one is correct:

(a) Dark

(b) Bright

(c) Blue

(d) Red

52. Michelson interferometer can be used to find the choose which one is correct:

(a) Wavelength of light

(b) Wavelength of sound

(c) Velocity of sound

(d) Velocity of light

53. The Michelson formula for displacement L is choose which one is correct:

(a) L = m

(b) L = 2m

(c) L = 2m

(d) L =

54. Michelson interferometer was devised in choose which one is correct:

(a) 1987

(b) 1881

(c) 1687

(d) 1789

55. When one mirror of a Michelson interferometer is move a distance of 0.5 mm, 2000 fringes are observed, the wavelength of light used is choose which one is correct:

(a) 2000 Ao

(b) 1000 cm

(c) 5000 Ao

(d) None of these

56. The property of bending light when it passes from one medium to another medium is known as choose which one is correct:

(a) Dispersion of light

(b) Diffraction of light

(c) Reflection of light

(d) None of these

57. Diffraction effects are choose which one is correct:

(a) More for sharp edges

(b) Less for cylindrical

(c) Less for round edge

(d) Less for sharp edge

58. We get light inside a room in a day time due to choose which one is correct:

(a) Diffraction

(b) Refraction

(c) Interference

(d) Polarized

59. Diffraction effects was discovered in 1801 by choose which one is correct:

(a) Newton

(b) Henry

(c) Huygen

(d) W.L Bragg

60. if A glass plate having a large number of close parallel equidistant slits mechanically rules on it will known as choose which one is correct:

(a) Diffraction

(b) Diffraction grating

(c) Fring spacing

(d) All of the above

61. A diffraction grating has 500 lines per mm. Its grating element will be choose which one is correct:

(a) 500 mm

(b) 5 x 10-3 mm

(c) 2 x 10-3 mm

(d) 5 x 10mm

62. The formula for grating element is choose which one is correct:

(a) d sin 0 =

(b) d sin 0 =

(c) d sin 0 =

(d) d sin 0 =

63. The condition for constructive interference in case of diffraction grating choose which one is correct:

(a) d sin 0 =

(b) 2d sin 0 =

(c) d sin 0 =

(d) d sin 0 =

64. Interference effects of light were verified by choose which one is correct:

(a) Thomas young

(b) Newton

(c) Einstein

(d) W.L Bragg

65. A fringe is a path of choose which one is correct:

(a) Constant phase

(b) Constant amplitude

(c) Same wavelength

(d) None of these

66. The main advantage of a grating over young’s apparatus is the choose which one is correct:

(a) Absence of bright light

(b) Greater deviation of light

(c) Absence of dark fringes

(d) Sharpness of bright lines

67. Michelson interferometer is based on the principle of choose which one is correct:

(a) Division of wavefronts

(b) Division of amplitude

(d) None of these

68. The blue of the sky is due to choose which one is correct:

(a) Polarization

(b) Reflection

(c) Refraction

(d) Scattering

69. The velocity of light was accurately measured by choose which one is correct:

(a) Newton

(c) Michelson

(d) Young

70. The wavelength of X-rays is choose which one is correct:

(a) 1000 Ao

(b) 10 Ao

(c) 1 Ao

(d) 100 Ao

71. Interference and diffraction of light support the choose which one is correct:

(a) Particle nature Of light

(b) Quantum nature of light

(c) Transverse nature of light

(d) Wave nature of light

72. Polarization of light shows that light is choose which one is correct:

(a) Extremely short wavelength

(b) Transverse waves

(c) Longitudinal waves

(d) Corpuscular in nature

73. Polarization of light takes place in choose which one is correct:

(a) Transverse waves

(b) Longitudinal waves

(c) Sound waves

(d) None of these

74. The polarization of an electromagnetic waves is determined by which among the following one choose which one is correct:

(a) Electric field

(b) Magnetic field

(c) Both electric and magnetic

(d) The direction of waves

75. A polarized is choose which one is correct:

(a) A light filter

(b) To analysed polarized light

(c) Used in polarimeter

76. Which one of the following cannot be polarized choose which one is correct:

(a) Sound waves

(c) Ultraviolet rays

(d) X-rays

77. One angstrom is equal to choose which one is correct:

(a) 10-6 m

(b) 10-8 nm

(c) 10 10 nm

(d) 10-8 cm

78. Diffraction is a special type of choose which one is correct:

(a) Interference

(b) Reflection

(c) Polarization

(d) None of these

79. Young’s double slit experiment proves choose which one is correct:

(a) Dual nature of light

(b) Particle nature of light

(c) Wave nature of light

(d) None of these

80. Two light waves which are not coherent cannot choose which one is correct:

(a) Be interference

(b) Be diffracted

(c) Be polarized in the same plane

(d) None of these

81. Light on passing through a Polaroid is choose which one is correct:

(a) Unpolarized

(b) Plane polarized

(c) Elliptically polarized

(d) Circularly polarized

82. Longitudinal waves do not exhibit choose which one is correct:

(a) Diffraction

(b) Polarization

(c) Reflection

(d) Refraction

83. Light has choose which one is correct:

(a) Particle nature

(b) Wave nature

(c) Dual nature

(d) None of these

84. Light waves are choose which one is correct:

(a) Longitudinal waves

(b) Transverse waves

(c) Compressional waves

(d) none of these

85. Wave length of light on the average is given by choose which one is correct:

(a) 10-9

(b)10-10

(c) 10-4

(d) 10-6

86. Light waves are choose which one is correct:

(a) Mechanical waves

(b) Electromagnetic waves

(c) Matter waves

(d) None of these

87. Monochromatic light means waves of choose which one is correct:

(a) Same colour

(b) Same wavelength

(c) Same frequency

(d) All of these

88. The path difference ‘d’ for constructive interference should be choose which one is correct:

(a) d =

(b) d =

(c) d =

(d) d =

89. The equation 2d sin 0 = denotes choose which one is correct:

(a) Huygen’s principle

(b) Young’s double slit experiment

(c) Brogg’s equation

(d) Diffraction grating equation

90. Ultra-violet rays differ from x-rays in that ultraviolet rays choose which one is correct:

(a) cannot be diffracted

(b) cannot be polarized

(c) do not affect a photo-graphic plate

(d) have a lower frequency

91. Which one of the following cannot be polarized choose which one is correct?

(b) Ultraviolet rays

(c) X-rays

(d) Sound waves

92. For which of the following colours will the fringe width be minimum in the double-slit experiment choose which one is correct:

(a) Violet

(b) Red

(c) Green

(d) Yellow

93. A diver in a lake wants to signal his distress to a person sitting on the edge of the lake flashing his water proof torch. He should direct the beam.

(a) Vertically upwards

(b) Horizontally

(c) At angle to the vertical which is slightly less than the critical angle

(d) At an angle to the vertical which is slightly more than critical angle

94. If The least distance of distinct vision is 25 cm. The focal length of a convex lens is 5 cm. It could be act as a simple microscope of magnifying power which one is correct

(a) 4

(b) 5

(c) 6

(d) 3

95. The index of refraction of diamond is 2.0 velocity of light in diamond in m/sec. is choose which one is correct:

(a) 6 x 108

(b) 3 x 108

(c) 2 x 108

(d) 1.5 x 108

96. Light reaches the earth from sun in nearly choose which one is correct:

(a) 15 minutes

(b) 10 minutes

(c) 8 minutes

(d) 8 minutes 20 second

97. Longitudinal waves do not exhibit (show) choose which one is correct:

(a) Reflection

(b) Refraction

(c) Diffraction

(d) Polarisation

98. The danger signals are red while the eye is more sensitive to yellow because what among the following options choose which one is correct:

(a) Scattering in yellow colour is less than that of red

(b) Red light is longer in wavelength than yellow light

(c) Scattering in red is less than in yellow

(d) Red colour has greater frequency than yellow light

99. When crest of one wave falls over the crest of the other waves, this phenomenon is known as choose which one is correct:

(a) Destructive interference

(b) Constructive interference

(c) Dispersion

(d) Polarisation

100. In Young’s double experiment, if white light is used choose which one is correct:

(a) Bright fringes will be seen

(b) Dark fringes will be seen

(c) Alternate dark and bright fringes will be seen

(d) No interference fringes will be seen

101. In Young’s double slit experiment, if the distance between the slits is doubled and distance between the slits and the screen is halved, the fringe width or spacing will be one among the following option choose which one is correct:

(a) Half

(b) Double

(c) Four times

(d) One fourth