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प्रश्न
Write an Explanation.
Critical angle
उत्तर
For a particular value of i (angle of incidence) for which, the value of r (angle of refraction) becomes equal to 90°, is called the critical angle.
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संबंधित प्रश्न
A narrow beam PQ of white light is passing through a glass prism ABC as shown in the diagram.
Trace it on your answer sheet and show the path of the emergent beam as observed on the screen DE.
(i) Write the name and cause of the phenomenon observed.
(ii) Where else in nature is this phenomenon observed?
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Study the following figure in which a student has marked the angle of incidence (∠i), angle of refraction (∠r), angle of emergence (∠e), angle of prism (∠A) and the angle of deviation (∠D). The correctly marked angles are
(a) ∠A and ∠i
(b) ∠A, ∠i and ∠r
(c) ∠A, ∠i, ∠e and ∠D
(d) ∠A, ∠i, ∠r and ∠D
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