Question

define angle of incidence​

Answer 1

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The angle of incidence is the angle between a ray incident on a surface and the line perpendicular to the surface at the point of incidence, called the normal.

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Answer 2

In Physics

A ray of light hits a surface at a point. The angle between the normal and the ray of light is called the angle of incidence.

You measure the angle from the normal, which is 0 degrees, to the ray of light.

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