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1. Homework Statement
Monochromatic light, at normal incidence, strikes a thin film in air. If λ denotes the wavelength in the film, what is the thinnest film in which the reflected light will be a maximum?
2. Homework Equations
n air ∠ n glass
so at the first reflection it will cuase a 180° ray out of phase while the second ray refected from the inside it will stay inphase because n air ∠ n glass
so for constructive interference: 2L=odd number*λ/2
3. The Attempt at a Solution
least odd number is one , so L=λ/4 ?? why it is incorrect
Monochromatic light, at normal incidence, strikes a thin film in air. If λ denotes the wavelength in the film, what is the thinnest film in which the reflected light will be a maximum?
A
λ/4
B
3λ/4
C
λ
D
much less than λ
E
λ/2
2. Homework Equations
n air ∠ n glass
so at the first reflection it will cuase a 180° ray out of phase while the second ray refected from the inside it will stay inphase because n air ∠ n glass
so for constructive interference: 2L=odd number*λ/2
3. The Attempt at a Solution
least odd number is one , so L=λ/4 ?? why it is incorrect
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