Aray diagram is shown.
what does the letter x represent?

angle of incidence
angle of reflection
normal
medium

Angle of incidence

Explanation:

The diagram shows the reflection of a light ray.

When a light ray undergoes reflection:

- The incident ray, the reflected ray and the normal to the surface all lie in the same plane

- The angle of reflection is equal to the angle of incidence

The two angles are defined as follows:

- The angle of incidence is the angle between the incident ray and the normal to the surface (1)

- The angle of reflection is the angle between the reflected ray and the normal to the surface

In the picture, we see that the angle marked with X corresponds to the angle defined in (1), so it is the angle of incidence.

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