If ray travelling in air is incident on a transparent medium as shown in the diagram, the refractive index of the medium is given as
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Correct Answer: Option A
Explanation:
\(n = \frac{sin i}{sin r}\)
\(i = 90 - \alpha\)
\(\therefore n = \frac{sin 90 - \alpha}{sin \beta}\)
⇒ \(n = \frac{cos \alpha}{sin \beta}\)
\(n = \frac{sin i}{sin r}\)
\(i = 90 - \alpha\)
\(\therefore n = \frac{sin 90 - \alpha}{sin \beta}\)
⇒ \(n = \frac{cos \alpha}{sin \beta}\)