
OPTICS
1. _____ is a form of energy which travels in the form of waves
Light
2. The path of light is called ____
Ray of light
3. Group of rays are called as_____
Beam of light
4. Any object which gives out light are termed as _____
Source of light
5. Some of the sources emit their own light and they are called as____
Luminous objects
6. All the stars, including the Sun, are examples for _______
Luminous objects
7. Light always travels along a ______” line
Straight
8.The speed of light in vacuum or air is____
c = 3 × 108 ms–1.
9. Different coloured light has ______ wavelength and frequency
Different
10. ____light has the lowest wavelength
Violet
11._____light has the highest wavelength.
Red
12. When a ray of light travels from one transparent medium into another obliquely,
the path of the light undergoes
Deviation
13._______takes place due to the difference in the velocity of light in different media
Refraction
14. The velocity of light is____ in a
Rarer medium
15. The velocity of light is____ in a denser medium
Less
16. The incident ray, the refracted ray of light and the normal to the refracting surface all lie in the ____ plane.
Same
17. Second law of refraction is also known as ______
Snell’s law.
18. When light travels from a denser medium into a rarer medium, the refracted ray is _____away from the normal drawn to the interface.
Bent
19. If a source of light produces a light of single colour, it is known as _____
Monochromatic source
20. When a beam of white light or composite light is refracted through any transparent media such as glass or water, it is split into its component colours. This phenomenon is called as
Dispersion of light
21. The band of colours is termed as____
Spectrum
22. Angle of refraction is the smallest for ___
Red
23. Angle of refraction is the highest for
24. The interacting particle of the medium is called as_____ Scatterer
25. The refractive index of a medium is dependent on the _______of the light.
Wavelength
26. When sunlight enters the Earth’s atmosphere, the atoms and molecules of different gases present in the atmosphere refract the light in all possible directions. This is called as____
‘Scattering of light’.
27. The interacting particle of the medium is called as_____
Scatterer
28. If the energy of the incident beam of light and the scattered beam of light are same, then it is called as
Elastic scattering
29. If the energy of the incident beam of light and the scattered beam of light are not same, then it is called as____
Inelastic scattering’.
30. The scattering of sunlight by the atoms or molecules of the gases in the earth’s atmosphere is known as _______
Rayleigh scattering.
31.____scattering takes place when the diameter of the scatterer is similar to or larger than the wavelength of the incident light.
Mie
32. _______ is caused by pollen, dust, smoke, water droplets, and other particles in
the lower portion of the atmosphere.
Mie scattering
33.______ is responsible for the white appearance of the clouds.
Mie scattering
34. The scattering of light rays by the colloidal particles in the colloidal solution is
called ______
Tyndall Scattering or Tyndall Effect.
35. _______Scattering is defined as “The interaction of light ray with the particles of pure liquids or transparent solids, which leads to a change in wavelength or frequency.”
Raman
36. The spectral lines having frequency equal to the incident ray frequency is called _____
‘Rayleigh line
37. The spectral lines which are having frequencies other than the incident ray
frequency are called
‘Raman lines’.
38. A _______is an optically transparent medium bounded by two spherical refracting surfaces or one plane and one spherical surface
Lens
39. Convex lens is also called as
Converging lens
40. Concave lens is also called as
Diverging lens
41. If one of the faces of a bi-convex lens is plane, it is known as a_____
Planoconvex lens.
42. If one of the faces of a bi-concave lens is plane, it is known as a ______
Plano-concave lens.
43. When an object is placed in front of a lens, the ______from the object fall on the lens Light rays
44. ________lenses are used as camera lenses
Convex lenses
45. ________are used as magnifying lenses
Convex
46. ________are used in making microscope, telescope and slide projectors
Convex lenses
47. Convex lensrs are used to correct the defect of vision called
Hypermetropia
48. Concave lenses are used as eye lens of _______
Galilean Telescope’
49. ________are used in wide angle spy hole in doors.
Concave lenses
50. ____ are used to correct the defect of vision called ‘myopia
Concave lenses
51. All lenses are made up of ________materials
Transperant
52. When a ray of light falls on a lens, the ability to converge or diverge these light rays depends on the _____of the lens.
Focal length
53. The ability of a lens to converge (convex lens) or diverge (concave lens) is called as its____
Power
54. The SI unit of power of a lens is ____
Dioptre
55. The power of a ____lens is taken as positive
Convex
56. The power of a____ lens is taken, as negative.
Concave
57._____is a converging lens.
Convex lens
58. _____ is a diverging lens
Concave lens
59. The eye ball is approximately spherical in shape with a diameter of about ____
2.3 cm
60. _____protects the internal parts of the eye
Sclera
61.____ is the thin and transparent layer on the front surface of the eyeball
Cornea
62. ____ is the coloured part of the eye
Iris
63. ______controls amount of light entering into the
pupil like camera aperture.
Iris
64.____is the centre part of the Iris. It is the pathway for the light to retina.
Pupil
65. ______is the back surface of the eye. It is the most sensitive part of human eye, on which real and inverted image of objects is formed.
Retina
66. Eye lens is fixed between the______
Ciliary muscles
67. _____ is made of a flexible, jelly-like material
Eye lens
68. The minimum distance required to see the objects distinctly without strain is called ____distance of distinct vision
69. A normal human eye can clearly see all the objects placed between _____ and infinity
25cm
70. _____ also known as short sightedness
Myopia
71. ______, also known as long sightedness, occurs due to the shortening of
Eye ball.
Hypermeteropia
72. Some persons may have both the defects of vision – myopia as well as hypermetropia. This can be corrected by Bifocal lenses
73. In this defect, eye cannot see parallel and horizontal lines clearly
Astigmatism
74. Simple microscope has a convex lens of short_____
Focal length.
75. _____ are used by watch repairers and jewellers.
Simple microscope
76. _____is used to observe finger prints in the field of
forensic science.
Simple microscope
77. A ______ microscope consists of two
convex lenses
Compound
78. A _______ microscope is one of the best instrument for measuring very small length with high degree of accuracy at the order of 0.01mm.
Travelling
79. ______works based on the principle of vernier. Its least count is 0.01 mm
80. _______is an optical instrument to see
the distant objects
Telescope
81.The first telescope was invented by _____ in 1608
Johann Lippershey
82. ______ is used to view heavenly bodies like stars, planets galaxies and satellites.
Astronomical telescope