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Hi there.
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So for this problem, we are told that a non -reflecting coating of magnesium fluoride of indesive refraption of 1 .38 covers the glass with an index of refraption of 1 .52 of a camera lens.
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Now, assuming that the coating prevents reflection of yellow -green lined, so we know that the wavelength associated with that color of light is 500.
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165 nanometers.
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So the question is to determine the minimum non -zero thickness that the coating can have.
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So in this case, what we have is a problem for destructive interference, because as the problem states, we need to find the thickness so that the coating prevents the yellow -green line to the reflection of yellow -green lines.
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Line.
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So the first thing that we are going to do is to draw the diagram that is convenient to solve this type of problems.
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So we have in here two surfaces because we have we have in here we have the index of refraption of err because that is the first medium.
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The next medium is the indies of refraption of coding.
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Remember that those values are given.
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For earth we know that that value is just simply one.
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For coding, we are given 1 .38.
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And for glass, which is the one at the bottom, is equal to 1 .52.
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Now, we have a rate of light that is incident in here.
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We have some reflection and some refraption in here, just like this.
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Then in this other change of surface or median, we have another reflection, and then we will have something like this.
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So that's a situation that we have.
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Remember that this is a rate of light with the wavelength that we are given.
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And this is the value that we need to update the thickness so that the two rates of light that are reflected.
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Are reflected, then cancel is shorter to produce that destructive interference.
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So that's what we need to obtain from this...