JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A light wave travelling linearly in a medium of dielectric constant \(4,\) incident on the horizontal interface separating medium with air. The angle of incidence for which the total intensity of incident wave will be reflected back into the same medium will be (Given : relative permeability of medium \(\mu_{ s }=1)\)
- A \(10\)
- B \(20\)
- C \(30\)
- D \(60\)
Answer & Solution
Correct Answer
(D) \(60\)
Step-by-step Solution
Detailed explanation
For total internal reflection, i \(>\theta_{ C }\) \(\Rightarrow \sin i>\sin \theta_{C}\) \(\Rightarrow \sin i>\frac{\mu_{R}}{\mu_{D}}\)............\((1)\) Also \(\mu=\sqrt{\mu_{ r } \epsilon_{ T }}\)…
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