Given :
The light rays in the incident ray originate at 20º from the surface.
To Find :
The angle for the incident ray.
Solution :
We know angle of incidence is measured from perpendicular to the surface .
So,
[tex]\theta_i = 90^o - 20^o\\\\\theta_i = 70^o[/tex]
Now, we know by law of reflection :
Angle of reflection = Angle of incident
[tex]\theta_r = 70^o[/tex]
Therefore, the angle of incident and reflection is 70° each.
