Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents

Your guest activity stays on this device

Sign in to save progress →
Sign in

Wave Optics question

2022 · Q147
Guest · filters and generic practice availableBrowsing as a guest · PYQ filters and generic practice are available. Sign in only for personalised features and saved progress.
  1. PYQ Library
  2. /NEET
  3. /Physics
  4. /Wave Optics
  5. /2022 · Q147

Wave Optics question

2022 · Q147

NEETPhysicsWave OpticsMCQ+4 / −1

In a Young's double slit experiment, a student observes 8 fringes in a certain segment of screen when a monochromatic light of 600 nm wavelength is used. If the wavelength of light is changed to 400 nm, then the number of fringes he would observe in the same region of the screen is

  1. A
    6
  2. B
    8
  3. C
    9
  4. D
    12
View written solutionFree

Correct answer: D

$$\beta = {{\lambda D} \over d}$$

Let length of segment of screen = l

$$ \Rightarrow l = 8{\beta _1} = {{8{\lambda _1}D} \over d}$$ ..... (1)

and $$ l = n{\beta _2} = {{n{\lambda _2}D} \over d}$$ .... (2)

from (1) and (2)

$$8{\lambda _1} = n{\lambda _2}$$

8(600 nm) = n(400 nm)

n = 12

PreviousNext

More from Wave Optics

  • Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is :2020 · MCQ
  • In Young's double slit experiment, if the separation between coherent sources is halved and the distance of the screen from the coherent sources is doubled, then the fringe width becomes :2020 · MCQ
  • In a double slit experiment, when light of wavelength 400 nm was used, the angular width of the first minima formed on a screen placed 1m away, was found to be 0.2o. What will be the angular width of the first minima, (μwater = 4/3)…2019 · MCQ
  • In Young’s double slit experiment the separation d between the slits is 2 mm, the wavelength λ of the light used is 5896 A0​ and distance D between the screen and slits is 100 cm. It is found that the angular…2018 · MCQ
  • Unpolarised light is incident from air on a plane surface of a material of refractive index μ. At a particular angle of incidence i, it is found that the reflected and refracted rays are perpendicular to each other. Which of the…2018 · MCQ
  • Young's double slit experiment is first performed in air and then in a medium other than air. It is found that 8th bright fringe in the medium lies where 5th dark fringe lies in air. The refractive index of the medium is nearly2017 · MCQ
  • The ratio of resolving powers of an optical microscope for two wavelength λ1 = 4000 A∘​ and λ2​ = 6000 A∘​ is2017 · MCQ
  • Two polaroids P1 and P2 are placed with their axis perpendicular to each other. Unpolarised light I0 is incident on P1. A third polaroid P3 is kept in between P1 and P2 such that its axis makes an angle 45o with that of P1. The intensity…2017 · MCQ