Browse by Stream
Discuss Doubts
Home
Search for Exam, Articles, Questions
get app
Go To Your Study Dashboard
  1. Home
  2. In a Youngs double slit experiment
# Engineering

In a Young's double slit experiment, slits are separated by 0.5 mm, and the screen is placed 150 cm away. A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes on the screen. The least distance from the common central maximum to the point where the bright fringes due to both the wavelengths coincide is

Answers (1)
A Abhishek Sahu

As we learnt in

Young Double Slit Experiment -

- wherein

y=\Delta x\cdot \left ( \frac{D}{d} \right )

y= Distance of a point on screen from central maxima

\Delta x= Path difference at that point

 

 

Ref y be the distance from the central maximum to the point where the bright fringes due to both the wavelength coincides

For \lambda_{1},  y=\frac{m\lambda_{1}D}{d}, 

for  \lambda_{2},   y=\frac{n\lambda_{2}D}{d}

\therefore\ \; m \lambda_{1}=n\lambda_{2}

\Rightarrow\ \; \frac{m}{n}= \frac{\lambda_{2}}{\lambda_{1}}=\frac{620}{650}=\frac{4}{5}

i.e. with respect to central maximum 4th bright fringe of \lambda_{1} coincides with 5th bright fringe of \lambda_{2}

y=\frac{4\times 650\times 10^{-9}\times 1.5}{0.5\times 10^{-3}}m

y=7.8\times10^{-3}m   or     y = 7.8 mm

Similar Questions

Preparation Products

Knockout JEE Main July 2020

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 12999/- ₹ 6999/-
Buy Now
Rank Booster JEE Main 2020

This course will help student to be better prepared and study in the right direction for JEE Main..

₹ 9999/- ₹ 4999/-
Buy Now
Test Series JEE Main July 2020

Take chapter-wise, subject-wise and Complete syllabus mock tests and get in depth analysis of your test..

₹ 4999/- ₹ 1999/-
Buy Now
Knockout JEE Main April 2021

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 17999/- ₹ 11999/-
Buy Now
Knockout JEE Main April 2022

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 34999/- ₹ 19999/-
Buy Now
Exams
Articles
Questions