Solved Problems on Angle of Incidence

Example 1. Find the angle of incidence and the angle of reflection for the ray of light striking the plane reflecting surface at 60°.

Solution:

Angle of incidence = 90°- 60° = 30°

As we know that, angle of incidence = angle of reflection,

Therefore, Angle of reflection = 30°

Hence, the angle of reflection for the ray of light striking the plane reflective surface at 60° is 30°.

Example 2. A ray of light strikes the plane reflective surface at an angle of 57. Calculate:

(i) The angle of incidence (i)

(ii) The angle of reflection (r)

(iii) The angle created by the reflected ray and the surface (q).

(iv) The angle formed between the incident ray and the ray that is reflected from the surface.

Solution:

From the diagram drawn above,

The angle of incidence = 90° – 57° = 33°

According to the law of reflection, the angle of incidence = the angle of reflection. Hence,

⇒ ∠r = ∠i = 33°

The angle created between the reflected ray and the reflective surface can be calculated as,

⇒ ∠q = 90 – ∠r = 90° – 33° = 57°

Now, the angle between the incident and the reflected rays = 33° + 33° = 66°

Angle of incidence is the angle created between a ray propagating on a surface and the line normal to the point of occurrence on the same surface. The manner in which the light is reflected back to the observer after it strikes a mirror is an excellent demonstration of how reflection works.

In this article, we will learn more about what the angle of Incidence is, the formula for the angle of incidence, examples related to the angle of incidence, the difference between the angle of incidence and the angle of reflection, and some of the frequently asked questions related to it.