JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 3 August 2021, Shift 2, Physics Q27

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

In Young's double slit experiment, 58 fringes are observed in the field of view when a light of wavelength 6000

\mathrm{\AA}

was used. Number of fringes that can be viewed, if another light of wavelength 4000

\mathrm{\AA}

is used are

\underline{\hspace{2em}}

Official answer

NTA final key.

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

Same idea in other shifts

Asked 7× in all

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
25 Jul 2021, Shift 1 · Q8In the Young's double slit experiment, the distance between the slits varies in time as $d(t)=d_0+a_0\sin\omega t$ ; where $d_0$ , $\omega$ …MediumSingle correct
18 Mar 2021, Shift 1 · Q7In Young's double slit arrangement, slits are separated by a gap of 0.5 mm, and the screen is placed at a distance of 0.5 m from them. The…EasySingle correct
9 Jan 2020, Shift 2 · Q24In a Young's double slit experiment 15 fringes are observed on a small portion of the screen when light of wavelength 500 nm is used. Ten…EasyNumerical value

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 42 of the 174 JEE Main shifts held from 2017 to 2026.