Question) A glass prism of reflective 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 the face BC if .
Let 0c(theta) be critical angle at BC then
sin 0c= 4/3 / 3/2 = 8/9
Also we know that TIR will take place if i>0(theta)
or in this case
0>0c
=> sin0>8/9
