Question

A ray of light is reflected by two parallel plane mirrors $X$ and $Y$.
Which statement is correct?

• A. The angle of incidence at mirror $X$ is ${30}^{\circ }$
• B. The angle of incidence at mirror $Y$ is ${60}^{\circ }$
• C. The angle of reflection at mirror $X$ is ${120}^{\circ }$
• D. The angle of reflection at mirror $Y$ is $0^{\circ }$

Answer 1

The correct option is B The angle of incidence at mirror $Y$ is ${60}^{\circ }$

Angle of Incidence at mirror X is $={90}^{\circ }-{30}^{\circ }={60}^{\circ }$

Angle of Incidence at mirror Y is $={90}^{\circ }-{30}^{\circ }={60}^{\circ }$