Q

What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray ?

Q13. What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray?

$\\Angle \ of \ incidence \ = \ Angle \ of \ reflection \\Angle \ of \ incidence \ + \ Angle \ of \ reflection \ = \ 90\degree \\ 2 \times Angle \ of \ incidence \ = \ 90\degree \\ Angle \ of \ incidence \ = \ 90\degree\div \2 \\ Angle \ of \ incidence \ = \45\degree$