A soap film of thickness 0.0011 mm appears dark when seen by the reflected light of wavelength 580 nm . What is the index of refraction of the soap solution, if it is known to be between 1.2 and 1.5 ?
For minimum reflection of light , 2 md = nl
Given that μ has a value in between 1.2 and 1.5.
⇒ When, n = 5,