Physics

Problem

Three identical soap films (

n=1.33

) in air have thicknesses

t_1=\frac{\lambda}{4n}

t_2=\frac{\lambda}{2n}

, and

t_3=\frac{3\lambda}{4n}

, where

\lambda

is the wavelength of normally incident light in vacuum. Which ranking correctly orders the reflected intensity at wavelength

\lambda

from greatest to least? a)

t_3 > t_1 > t_2

t_1 = t_3 > t_2

t_2 > t_1 = t_3

t_1 > t_3 > t_2