MCQ
The critical angle for diamond (refractive index $=2$ ) is
- AAbout $20^{\circ}$
- B$60^{\circ}$
- C$45^{\circ}$
- ✓$30^{\circ}$
✓
Answer
Correct option: D.
$30^{\circ}$
$\mu=\frac{1}{\sin C} \Rightarrow C=\sin ^{-1}\left(\frac{1}{2}\right)=30^{\circ}$
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