Ray Optics & Optical Instruments  MCQs

MCQs of Ray Optics & Optical Instruments

Showing 101 to 110 out of 143 Questions
101.
A prism of certain angle deviates the red and blue rays by 8° and 12° respectively. Another prism of the same angle deviates the red and blue rays by 10° and 14° respectively. The prism are small angled and made of different materials. The dispersive powers of the materials of the prisms are in the ratio of _____ .
(a) 5 : 6
(b) 9 : 11
(c) 6 : 5
(d) 11 : 9
Answer:

Option (c)

102.
Diameter of spherical mirror is 10 cm, what will be aperture of mirror ?
(a) 20 cm
(b) 10 cm
(c) 40 cm
(d) 5 cm
Answer:

Option (b)

103.
A liquid of refractive index n is filled in a tank. A plane mirror is kept at the bottom of the tank. A point like object (P) is kept at a height h from the mirror on the liquid surface. An observer observes the object and its image in the vertically downward direction from top. How much distance will observer note between P and its image ?
(a) 2n.h
(b) 2hn
(c) 2h(n - 1)
(d) h · 1 +1n
Answer:

Option (b)

104.
Depth of a well is 5.5 m and refractive index of water is 1.33. If viewed from the bottom, by how much height would the bottom of the well appear to be shifted up ?
(a) 5.5 m
(b) 2.75 m
(c) 4.13 m
(d) 1.37 m
Answer:

Option (d)

105.
A ray of light is travelling from a denser medium to rarer medium. For these media, the critical angle is C. The maximum possible deviation of the ray is _____ .
(a) π - 2
(b) π - 2c
(c) 2C
(d) π2 + C
Answer:

Option (b)

106.
The focal length of a thin lens made from the material of refractive index 1.5 is 20 cm. When it is placed in a liquid of refractive index 1.33, its focal length will be _____ cm.
(a) 80.81
(b) 45.48
(c) 60.25
(d) 78.23
Answer:

Option (d)

107.
A tank contains water upto a height of 30 cm and above it an oil up to another 30 cm height. _____ cm shifts in the position of bottom of the tank is observed when viewed from the above. Refractive indices of water and oil are 1.33 and 1.28 respectively.
(a) 7.44
(b) 6.46
(c) 14.02
(d) 6.95
Answer:

Option (c)

108.
A ray of light is incident normally on the surface of an equilateral prism made up of material with refractive index 1.5. The angle of deviation is _____ .
(a) 30°
(b) 45°
(c) 60°
(d) 75°
Answer:

Option (c)

109.
A ray incident at an angle i on the surface of a prism with very small prism angle A, and emerges normally from the opposite surface. If the refractive index of the prism is μ, the angle of incidence i is nearly equal to _____ .
(a) Aμ
(b) μA2
(c) A2μ
(d) μA
Answer:

Option (d)

110.
A small linear object of length b is placed on the axis of a concave mirror. The end of the object facing the mirror is at a distance u from the mirror. If f is the focal length of a mirror, the length of the object will be _____ approximately.
(a) bu - ff2
(b) bfu - f
(c) u - ff
(d) bfu - f2
Answer:

Option (d)

Showing 101 to 110 out of 143 Questions