Question

The phenomenon which produces colours in a soap bubble is due to:
1. Diffraction
2. Dispersion
3. Interference
4. Polarisation

Answer 1

Correct Answer - Option 3 : Interference

CONCEPT: 

• Interference is the phenomena in which two waves superimpose to form a resultant wave the intensity which is greater or smaller than superimposed waves.  
• Interference is of two types 
  • Constructive interference: The process in which the intensity and amplitude of the resultant wave are greater than two superimposed waves.
  • Destructive interference: The process in which the intensity and amplitude of the resultant wave are lesser than two superimposed waves.​​

EXPLANATION:

• The colours in a soap bubble are produced due to interference
• The colours are seen in a soap bubble due to the interference of light reflecting off from the front and back surfaces of the soap film.​ Hence, option 3 is the answer.