Question

What is the minimum (non-zero) thickness ttt of the film that produces a strong reflection for green light with a wavelength of 500 nmnm

Answer 1

Answer:

200 nm.

Explanation:

The minimum thickness can be found using the following equation:

$2t = \frac{m\lambda}{n}$

Where:

t: is the thickness =?

m: is the order of interference = 1 (since it is minimum)

n: is the refractive index = 1.25

λ: is the wavelength = 500 nm

$t = \frac{m\lambda}{2n} = \frac{500 nm}{2*1.25} = 200 nm$

Therefore, the minimum thickness is 200 nm.

I hope it helps you!