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