# A glass prism of refractive index 1.5 is immersed in water (refractive index 4/3). A light beam incident normally on the face AB is totally reflected

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A glass prism of refractive index 1.5 is immersed in water (refractive index 4/3). A light beam incident normally on the face AB is totally reflected to reach on the face BC if.

A. sintheta gt 8 //9
B. sintheta lt 2//3
C. 2//3 lt sintheta lt 8//9
D. none

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Critical angle from glass to water
mu_gsinC=mu_omegasin90^@
3/2sinC=4/3xx1impliessinC=8/9
T.I.R. takes place on AC i.e.
thetagtC
sinthetagtsinC
sinthetagt8//9