Question

A ray of light is incident at 50° on the middle of one of the
two mirrors arranged at an angle of 60° between them. The
ray then touches the second mirror, get reflected back to
the first mirror, making an angle of incidence of
(a) 50° (b) 60°
(c) 70° (d) 80
(ans - c ) -how?​

Answer 1

Answer:

c.70°

Let required angle be θ.

In Δ ABC

90° − θ + 140° + 20° = 180°

⇒ θ = 70°

❥Now you understand❥