11. What is meant by the interference of two light waves? Describe in detail what happens when a plane light wave passes through two slits spaced a small distance apart.

What is Young's experiment? Describe in detail what happens when light reflects from thet op and bottom surfaces of a thin film. What is thin-film interference? Work through the different special cases of thin-film interference, regarding the possible combinations of refractive index on either side of the thin film. What are Newton's rings?

Fig: 1