The reflected wave, incident wave and the normal to the reflecting surface:
in different planes
in same plane
in planes perpendicular to each other
incident and reflected waves are in the same plane while normal is in a perpendicular plane
According to the first law of reflection, the reflected wave, incident wave and the normal to the reflecting surface always lie on the same plane.
The angle of incidence and angle of reflection are equal only if the incident ray and the reflected ray are in the same plane and the normal is in a different plane.
The laws of reflection state that the incident ray, reflected ray and the normal to the surface of mirror lie in different planes.