Reflection and Mirrors - Mission RM1 Detailed Help

The diagram below depicts a ray of light reflecting off a planar surface. The angle of incidence is depicted by angle _____.


 
Definition of Angle of Incidence:
The angle of incidence is the angle made by the ray of light approaching a surface (incident ray) and the normal line drawn to the surface at the location where the ray contacts the surface.


 
A common mistake made by beginning physics students is to believe that the angle of incidence is the angle between the incident ray and the mirror surface. But don't be fooled! Angles of incidence (and reflection) are always measured between the ray of light and the normal line.