Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this? 1. Dispersion 2. Refraction 3. Internal reflection Select the correct Solution using the codes given below.
Explanation
Dispersion, Refraction and Internal reflection are all involved.
| Phenomenon | Role in rainbow formation | |------------|---------------------------| | Refraction | Sunlight bends when it enters the raindrop and again when it exits, changing direction at each air–water boundary. | | Dispersion | Different wavelengths refract by slightly different angles, so the white light spreads into its constituent colours inside the drop. | | Internal reflection | Part of the dispersed light reflects from the rear surface of the droplet and heads back toward the observer, making the coloured arc visible. |
Thus, the combined effect of Refraction → Dispersion → Internal Reflection → Refraction in order produces the familiar rainbow spectrum.
