Question

(a) A ray of light strikes the surface of a rectangular glass block such that the angle of incidence is (i) 0° (ii) 42°. Sketch a diagram to show the approximate path taken by the ray in each case as it passes through the glass block and emerges from it.

Answer 1

Angle of incidence 42° = critical angle of glass, the refracted ray makes angle of 90° and emerge parallel to the surface along BC.