# Thinnest film in which the reflected light will be a maximum?

#### vrobins1

1. Homework Statement

Monochromatic light, at normal incidence, strikes a thin film in air. If (lambda) denotes the wavelength in the film, what is the thinnest film in which he reflected light will be a maximum?

2. Homework Equations

2d = (m+1/2)(lambda/nfilm) for minimal reflection and

2d = m(lambda/nfilm) for max reflection

3. The Attempt at a Solution

I used the second formula above:

2d = m(lambda/n) and solved for d;
I got d = lambda/2n , but someone else in my class says it is lamba/4n,

Can anyone offer any insight? Thanks!!

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