Question

An intensity minimum is found for 450 nm light transmitted through a transparent film (n=1.20) in air.

(a) What is the minimum thickness of the film?

Answer 1

To find the minimum thickness of the film, we can use the equation: 2nt = (m + 0.5)λ, where t is the thickness of the film, n is the refractive index, m is the order of the minimum, and λ is the wavelength of light.

Step-by-step explanation:

To find the minimum thickness of the film, we can use the equation:

2nt = (m + 0.5)λ

Where t is the thickness of the film, n is the refractive index, m is the order of the minimum, and λ is the wavelength of light.

For this problem, we are given that the wavelength is 450 nm, the refractive index is 1.20, and we are looking for the minimum order, so m = 0. Plugging in these values, we get:

2(1.20)t = (0 + 0.5)(450 nm)

Simplifying the equation, we find:

t = 0.375 μm