What is the minimum thickness of coating which should be placed on a lens in order to minimize reflection of 566 nm light? The index of refraction of the coating material is 1.46 and the index of the glass is 1.71.

The  thickness is  

Explanation:

From the question we are told that

    The wavelength is  

     The  index of refraction of glass is  

     The index of refraction of the coating is  

Generally the condition for destructive interference is  

Here m is the order of the interference pattern and given from the question that we are considering minimizing  reflection  m = 0

t = thickness of the coating

substituting values

    =>    

8 meters above the spring

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