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Refraction Of Light Through A Prism

Question
ICSEENIPH12029779
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At what angle, a ray of light should be incident on the first face AB of a regular glass prism ABC so that the emergent ray grazes the adjacent face AC? See Figure 7 below. (Refractive Index of glass = 1.6)

At what angle, a ray of light should be incident on the first face AB

Solution

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Question
ICSEENIPH12029827
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For any prism, show that refractive index of its material is given by:


straight n space or space straight mu space equals space fraction numerator sin space open parentheses begin display style fraction numerator straight A space plus straight delta subscript straight m over denominator 2 end fraction end style close parentheses over denominator sin space open parentheses begin display style straight A over 2 end style close parentheses end fraction 
where the terms have their usual meaning.

Solution

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Here, 


i = Angle of incidence

e= Angle of emergence

A = refracting angle

r + r’ = Angle of a refraction

δ = deviation

i + e = A + δ                               ---(i)

A = r1+ r2                                              ---(ii)

Above relation connecting i. c., A + δ are shown above.

Under minimum deviation i = e, rt = r2 = r

From Eq. (i), we have

2 i = A + δ min

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Hence proved. 

Question
ICSEENIPH12029853
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A ray of light LM incident normally on the surface AC of an isosceles right angled prism ABC (where AB = BC) emerges along PQ, parallel to LM, shwon in Figure.
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What can you say about refractive index μ of the material of the prism?

Solution

∠A = angleC = 45°

∠ i = 45°

For total internal reflection to take place at faces,
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Question
ICSEENIPH12029873
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Calculate angle of minimum deviation (δm) for a regular glass prism. (Refractive index of glass = 1-6) 

Solution

Given,
n = 1.6

sin = ? 
We  know, 
n = fraction numerator sin space open parentheses begin display style fraction numerator straight A space plus space sin over denominator 2 end fraction end style close parentheses over denominator sin space straight A divided by 2 end fraction 
1.6 = fraction numerator sin space open parentheses begin display style fraction numerator 60 space plus space sin over denominator 2 end fraction end style close parentheses over denominator sin space open parentheses begin display style 60 over 2 end style close parentheses end fraction 
53.13 = fraction numerator 60 space plus space sin over denominator 2 end fraction 
   sin = 46.26o 

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