Explain how bright fringes arise in Young's double slit experiment

To answer this question, we need to think about 3 things: interference, phase and path difference

In the experiment, we have monochromatic light (from a laser) going through two slits and then bright and dark fringes appearing on the screen. (I will draw the experiment on the white board) 

What the monochromatic light means is that the light shining through the two slits act as two coherent sources of light (at the same frequency). In order for bright fringes to occur, the waves of light need to interfer constructively. This means that the displacement of the waves when they intefer with each other add together - they superimpose to make a larger amplitude ie the bright fringe. To interfer constructively like this, the waves must arrive together in phase and have a path difference which is a whole number of wavelengths (1 wavelength, 2 wavelengths etc)

HM
Answered by Harveer M. Physics tutor

3641 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A projectile is launched from ground level with a speed of 25 m/s at an angle of 42° to the horizontal. What is the horizontal distance from the starting point of the projectile when it hits the ground?


What is electromotive force (emf) and how can the emf of a battery be measured?


In one second a mass of 210 kg of air enters at A. The speed of this mass of air increases by 570 m s–1 as it passes through the engine. Calculate the force that the air exerts on the engine.


The braking distance of a road train travelling at 15m/s is 70m. Assuming that the same braking force is applied at all speeds, show that the braking distance of a road train when travelling at 25m/s is about 190m.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences