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What is the minimum thickness of thin fi...

What is the minimum thickness of thin film required for constructive interference in the reflected light through it ?
(Given, the refractive index of the film `=1.5,` wavelength of the lilght incident on the film `=600` nm.

A

100nm

B

200 nm

C

50 nm

D

200 nm

Text Solution

Verified by Experts

The correct Answer is:
A
Condition for constructive interference
`2mut= (2n+1) lambda//2`
For minimum thickness n=0
`t= (600 xx 10^(-9))/(4 xx 1.5) = 100 nm`
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