JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 26 August 2021, Shift 1, Physics Q27

Question 27 of 90 in this shift, Physics question 27 of 30, Section B.

White light is passed through a double slit and interference is observed on a screen 1.5 m away. The separation between the slits is 0.3 mm. The first violet and red fringes are formed 2.0 mm and 3.5 mm away from the central white fringes. The difference in wavelengths of red and voilet light is __________ nm.

Official answer

300

NTA final key.

Chapter: Wave Optics
Topic: Young's Double Slit
Idea tested: YDSE Fringe Width

Same idea in other shifts

Asked 14× in all

5 Apr 2024, Shift 1 · Q58In Young's double slit experiment, carried out with light of wavelength 5000 Å, the distance between the slits is 0.3 mm and the screen is…EasyNumerical value
8 Apr 2023, Shift 2 · Q46The width of fringe is 2 mm on the screen in a double slits experiment for the light of wavelength of 400 nm. The width of the fringe for…EasySingle correct
28 Jul 2022, Shift 1 · Q53In a Young's double slit experiment, a laser light of 560 nm produces an interference pattern with consecutive bright fringes' separation…EasyNumerical value
29 Jun 2022, Shift 1 · Q49Using Young's double slit experiment, a monochromatic light of wavelength 5000 $\mathrm{\AA}$ produces fringes of fringe width 0.5 mm. If…EasySingle correct
29 Jun 2022, Shift 2 · Q59In a double slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the plane of slits. If…MediumNumerical value
3 Aug 2021, Shift 2 · Q27In Young's double slit experiment, 58 fringes are observed in the field of view when a light of wavelength 6000 $\mathrm{\AA}$ was used.…EasyNumerical value
31 Aug 2021, Shift 2 · Q24In a Young's double slit experiment, the slits are separated by 0.3 mm and the screen is 1.5 m away from the plane of slits. Distance…EasyNumerical value
24 Feb 2021, Shift 2 · Q14If the source of light used in a Young's double slit experiment is changed from red to violet :EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.