Waves Optics  MCQs

MCQs of Waves Optics

Showing 121 to 130 out of 131 Questions
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121.
The limit of resolution of an optical instrument arises an account of _____
(a) interference
(b) polarisation
(c) photoelectric effect
(d) diffraction
Answer:

Option (d)

122.
If white light is used in diffraction at a single slit, the central maximum will be _____
(a) black
(b) blue
(c) red
(d) white
Answer:

Option (d)

123.
In the propagation of light waves, the angle between the plane of vibration & plane of polarisation is _____
(a) 90°
(b) 60°
(c) 30°
(d) 0°
Answer:

Option (a)

124.
When the light sources is moving towards an observer
(a) speed of light increases
(b) wavelength of light unchanged
(c) wavelength of light increases
(d) wavelength of light decreases
Answer:

Option (d)

125.
Light waves travel in vacuum along X - axis, which of the following may represent wave fronts ?
(a) x = a
(b) y = a
(c) z = a
(d) x + y + z = a
Answer:

Option (a)

126.
For which property electrons are used in electron microscope ?
(a) Wave nature
(b) Negative charge
(c) Spin
(d) None of these
Answer:

Option (a)

127.
In the phenomenon of diffraction of light, when blue light is used in the experiment instead of red light then _____
(a) fringes will become broader
(b) no charge in fringe width
(c) fringes will become narrower
(d) none of these.
Answer:

Option (c)

128.
If a source of light is moving away from a stationary observer, then frequency of light wave appears to change because of _____
(a) doppler's effect
(b) interference
(c) diffraction
(d) none of these
Answer:

Option (a)

129.
Which does not show polarisation ?
(a) Longitudinal wave in gas
(b) Transverse waves in gas
(c) Both (A) and (B)
(d) None of these
Answer:

Option (d)

130.
What should be refractive index of transparent medium to be invisible in vacuum ?
(a) < 1
(b) 1
(c) > 1
(d) none of these
Answer:

Option (b)

Showing 121 to 130 out of 131 Questions
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