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A light of wavelength 5890Å falls normal...

A light of wavelength `5890Å` falls normally on a thin air film. The minimum thickness of the film such that the film appears dark in reflected light is

A

`2.945xx10^(-7)m`

B

`3.945xx10^(-7)m`

C

`4.95xx10^(-7)m`

D

`1.945xx10^(-7)m`

Text Solution

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The correct Answer is:
A
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