PYQ Vault
EbooksTutor

New fringe width when the wavelength, slit separation or screen distance changes

This type of question, asked 5 times: 29 Jun 2022, 28 Jul 2022, 8 Apr 2023, 4 Apr 2025, 23 Jan 2026 S1. All 6 questions below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    29 Jun 2022

    19
    Using Young's double slit experiment, a monochromatic light of wavelength 5000Å5000\text{Å} produces fringes of fringe width 0.5 mm0.5\text{ }mm. If another monochromatic light of wavelength 6000Å6000\text{Å} is used and the separation between the slits is doubled, then the new fringe width will be:

    Tap an option to check your answer.

  2. Question 2

    29 Jun 2022

    119
    In a double slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the plane of slits. If the screen is moved by 5×10−2 m5 \times10^{- 2}\text{ }m towards the slits, the change in fringe width is 3×10−3 cm3 \times10^{- 3}\text{ }cm. If the distance between the slits is 1 mm1\text{ }mm, then the wavelength of the light will be ____\_\_\_\_ nm.

  3. Question 3

    28 Jul 2022

    23
    In a Young's double slit experiment, a laser light of 560 nm560\text{ }nm produces an interference pattern with consecutive bright fringes' separation of 7.2 mm7.2\text{ }mm. Now another light is used to produce an interference pattern with consecutive bright fringes' separation of 8.1 mm8.1\text{ }mm. The wavelength of second light is ____\_\_\_\_ nm.

  4. Question 4

    8 Apr 2023

    105
    The width of fringe is 2 mm2\text{ }mm on the screen in a double slit experiment for the light of wavelength of 400 nm400\text{ }nm. The width of the fringe for the light of wavelength 600 nm600\text{ }nm will be:

    Tap an option to check your answer.

  5. Question 5

    4 Apr 2025

    5
    In a Young's double slit experiment, the slits are separated by 0.2 mm . If the slits separation is increased to 0.4 mm , the percentage change of the fringe width is:

    Tap an option to check your answer.

  6. Question 6

    23 Jan 2026 S1

    24
    In two separate Young's double-slit experimental set-ups, two monochromatic light sources of different wavelengths are used to get fringes of equal width. The ratios of the slit separations and that of the wavelengths of light used are 2:12:1 and 1:21:2 respectively. The corresponding ratio of the distances between the slits and the respective screens ( D1/D2D_{1}/D_{2} ) is ____\_\_\_\_.