Question

If a light ray strikes a crystal perpendicular to its crystal face, which statements are true according to Snell's law?(more than one answer)
A. The angle of incidence would be equal to the angle of refraction.
B. The angle of incidence would be equal to zero.
C. The angle of refraction would be equal to zero.
D. The light ray would be parallel to the normal.

Answer 1

I think all the ans.are correct because the condition given in ques. means angle of incidence is zero and angle of refraction is also zero(since angle is made by the respective rays with the normal and the light ray is perpendicular to the crystal surface)
This implies angle i=angle r=0 and the light is perpendicular to crystal surface which means the light ray is parallel to normal.
Thus A,B,C and D ...all are correct.

Answer 2

All answers are correct