Question

a ray of light falls normally on a plane mirror. what is its angle of incidence​

Answer 1

The law of reflection is that the angle of reflection is equal to the angle of incidence. ... When a ray of light falls normal to the plane of the mirror, it is perpendicular or a 90 degree angle. Thus the reflected ray will come directly back from the mirror toward the source of light.

Answer 2

Answer:

90 degree

Explanation:

ray of light is falling straightly on plane mirror so normally its angle of incidence be 90 degree