Question

Q7.Two plane mirrors M^1 and M^2 are placed at a right angle. A ray of light is incident on M^1 at P^1 and gets reflected from M^1 . It then gets reflected from M^2 at P^2 .
If OP^1 = OP^2 , then what is the angle of reflection of the ray at P^2 ?

Answer 1

Answer:

=90°−θ

β=θ

⟹θ+β+γ=180° (In △)

⟹θ+θ+γ=180°

∴γ=180°−2θ

∵δ=90°−γ

∴δ=90°−(180°−2θ)=2θ−90°

θ=90°−δ=90°−(2θ−90°)

⟹θ=180°−2θ

⟹3θ=180°

∴θ=60°