What is the minimum thickness of the air layer between two flat glass surfaces if the glass is to appear bright when 450 nm light is incident normally?
A) 57.0 nm
B) 113 nm
C) 170 nm
D) 226 nm

Question

Quizplus · Accepted Answer

The minimum thickness of the air layer between two flat glass surfaces for bright appearance is given by:

t = λ/4n

where 
λ is the wavelength of light (450 nm)
n is the refractive index of glass (1.5)

Substituting the values, we get:

t = (450 nm)/(4 x 1.5) = 113 nm

Therefore, the minimum thickness of the air layer between two flat glass surfaces for bright appearance when 450 nm light is incident normally is 113 nm, which is option B.

What Is the Minimum Thickness of the Air Layer Between