COMEDK · Physics · 25. Ray Optics
Light enters at an angle of incidence in a transparent rod of refractive index '\(n\)'. The least value of '\(n\)' for which the light once entered into it will not leave it through its lateral face whatsoever be the value of the angle of incidence is
- A 1.3
- B \(\sqrt{2}\)
- C 2
- D 1.5
Answer & Solution
Correct Answer
(B) \(\sqrt{2}\)
Step-by-step Solution
Detailed explanation
Let the refractive index of the rod be \(n\) and the refractive index of the surrounding medium be \(1\). Let the angle of incidence at the end face be \(i\) and the angle of refraction be \(r\). By Snell's law at the end face, \(1 \times \sin(i) = n \times \sin(r)\). The light…
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