Question

the angle of incidence at which a light ray does not undergo refraction

Answer 1

0 degrees is the answer

Answer 2

Answer:

Angle of Incidence = 90°

Explanation: Dear Student:

From Snell's law,

        c sinα =d sinβ

Where, c and d are refractive index.

c=4/3 (considering water 0

d = 1   (Vacuum)

4/3 sinα=1 sin90°

  sinα = 3/4

α = arc(sin3/4)

Hence,angle of incidence, α = arc(sin3/4)

Hope it helps

See the figure.