law of reflection

American  

noun

1. the principle that when a ray of light, radar pulse, or the like, is reflected from a smooth surface the angle of reflection is equal to the angle of incidence, and the incident ray, the reflected ray, and the normal to the surface at the point of incidence all lie in the same plane.

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Usage

What is the law of reflection? While it may sound like a form of meditation, the law of reflection is a principle about what light does when it hits a perfectly smooth surface, like a mirror. The law states that light will bounce off such a surface at the exact same angle it hit that surface at.

Example Sentences

Use the law of reflection to prove that the focal length of a mirror is half its radius of curvature.

From Textbooks • Aug. 12, 2015

We see the light coming from a direction determined by the law of reflection.

From Textbooks • Aug. 12, 2015

The law of reflection is illustrated in Figure 25.3, which also shows how the angles are measured relative to the perpendicular to the surface at the point where the light ray strikes.

From Textbooks • Aug. 12, 2015

By relying on the law of reflection and the idea that reflective surfaces can be used to form images, telescopes can be constructed using mirrors to distort the path of light.

From Textbooks • Aug. 12, 2015

One law of reflection is that, when a ray of light falls on a plane or spherical surface, it goes off at the same angle to the surface as it fell.

From Meteorology or Weather Explained by M'Pherson, J. G.