Q706
A thin oil film on a water surface appears coloured because of
A.
Reflection
B.
Interference
AnswerC.
Diffraction
D.
Polarization
Answer: Option B
Solution
Answer: Option B
Solution:
A thin oil film on a water surface appears coloured because of thin-film interference which involves the interference of light waves reflecting off the top surface of a film with the waves reflecting from the bottom surface. The refractive index of oil is larger than that of water, therefore the reflection on the back side occurs.