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**1. A nonreflective coating (n = 1.24) covers the glass (n = 1.52) of a camera lens. Assuming that the coating prevents reflection of yellow-green light (wavelength in vacuum = 564 nm), determine the minimum nonzero thickness that the coating can have.**

**2. wavelength of the light in the coating = wavelngth of light / n of coating**

desructive interference: 2t = (1,2...) wavelngth coating

t=thickness

desructive interference: 2t = (1,2...) wavelngth coating

t=thickness

**3. OK the wavelngth of the light through the coating is: 564/1.24 = 454.84**

I figured maybe that was all i needed and attempted to find t.

2t=1(454.84)

t= 227.42

this was not correct, so I next proceded to find the wavelength once through the film to the glass:

454.84/1.52 = 299.24 nm

The destructive interference for this is:

2t = (1) 299.24

t= 149.62 nm

This too was incorrect.

I even tried plugging in the original wavelength of 564 nm with the n of glass; 1.52, then solving for t. This gave me:

564/1.52 = 371.05

2t= (1) 371.05

t= 185.53

None of these were correct.

Any thoughts on where am I going wrong?

I figured maybe that was all i needed and attempted to find t.

2t=1(454.84)

t= 227.42

this was not correct, so I next proceded to find the wavelength once through the film to the glass:

454.84/1.52 = 299.24 nm

The destructive interference for this is:

2t = (1) 299.24

t= 149.62 nm

This too was incorrect.

I even tried plugging in the original wavelength of 564 nm with the n of glass; 1.52, then solving for t. This gave me:

564/1.52 = 371.05

2t= (1) 371.05

t= 185.53

None of these were correct.

Any thoughts on where am I going wrong?