13
Question Question 13
What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray?
Given,
∠i + ∠r = 90° where
∠i = angle of incident.
∠r = angle of reflection
According to the law of reflection,
∠i = ∠r
Substituting the above law in the given condition we get,
2∠i = 90°
∠i = = 45°
Therefore, angle of incidence = 45°.