alleryc=3×10^8, glass v=1.5×10^8 m/s. At 45° incidence to glass-air, the ray
ARefraction into outside air
BTotal internal reflection
CNormal emergence into air
DGrazing emergence along surface
Answer & Solution
Correct answer: B. Total internal reflection
The speed ratio gives n=2 and C=30°, so a 45° internal incidence exceeds the critical angle and produces TIR.
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