Two mirrors A and B are placed at right angles to each other

Two mirrors A and B are placed at right angles to each other as shown in Figure.

A ray of light incident on mirror A at an angle of 25° falls on mirror B after reflection. The angle of reflection for the ray reflected from mirror B would be

  1. 25°
  2. 50°
  3. 65°
  4. 115°

Answer

Angle of reflection for the ray reflected from mirror B will be 65° because figure below shows how reflected ray from mirror A forms incident ray on mirror B and then reflected back by an angle of 65°.

The correct option is C.