2024 Wave OpticsYoung's Double Slit Experiment Easy Question 1 of 8 in Young's Double Slit Experiment

If the monochromatic source in Young's double slit experiment is replaced by white light, then

A there will be a central bright white fringe surrounded by a few coloured fringes.
B all bright fringes will be of equal width.
C interference pattern will disappear.
D there will be a central dark fringe surrounded by a few coloured fringes.

The answer is A.

Solution

White light is a mixture of different wavelengths (colours). At the centre, the path difference is zero for all wavelengths, so all colours combine to give a central bright white fringe. Away from the centre, different colours have their maxima at different positions, so the surrounding fringes appear coloured, and only a few coloured fringes are visible.

Concept YDSE with white light source

Young's Double Slit Experiment in past papers

8 questions from this chapter have appeared across 8 exam years.