Question

In an interference experiment, monochromatic light is replaced by white light, we will see

Answer 1

Interfernce experiment

1. White light is made up of waves with a variety of wavelengths ranging from violet to red.
2. When monochromatic light is substituted with white light in Young's double-slit experiment, the waves of each wavelength generate their own interference patterns.
3. The influence of these patterns as a result is displayed on the screen. At the location R of the central fringe, the path distinction between waves ranging from S1 to S2 is zero, i.e. at the point R of the screen, the path difference will be 0.
   Hence, all waves in the same phase approach a middle point R.
4. As a result, the central fringe is white. As the fringe dimension, that is, the wavelength, increases, so do the colours designated by VIBGYOR, therefore certain colourful fringes are obtained in the order of colour VIBGYOR on each side of it.
5. The violet fringe appears first, followed by the red. When the fringes of various colours overlap at every point on the screen, the screen appears to be lighted uniformly.
6. Therefore, if we use white light instead of monochromatic light, the middle fringe is white, with numerous colourful fringes on either side in order VIBGYOR, while the rest screen seems uniformly illuminated.

Hence, in an interference experiment, monochromatic light is replaced by white light, we will see a few colored bands and then uniform illumination.