For light going from a medium of refractive index n to air, the critic…

Question

For light going from a medium of refractive index n to air, the critical angle i_c is given by:

Accepted Answer

B. sin i_c = 1/n

At the critical angle, r = 90°.
**Snell's law:** **n × sin i_c = 1 × sin 90° = 1 → sin i_c = 1/n**.
For water (n = 1.33): i_c ≈ 48.75°.
For diamond (n = 2.42): i_c ≈ 24.4° (small i_c → strong TIR → diamond sparkle).

Answer

sin i_c = n

Answer

cos i_c = n

Answer

tan i_c = 1/n

For light going from a medium of refractive index n to air, the critical angle i_c is given by:

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