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

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

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

From Textbooks • Aug. 12, 2015

These are the law of reflection, for situations in which light bounces off matter, and the law of refraction, for situations in which light passes through matter.

From Textbooks • Aug. 12, 2015

Figure 25.3 The law of reflection states that the angle of reflection equals the angle of incidence— θr = θi .

From Textbooks • Aug. 12, 2015

For more than a thousand years no step was taken in optics beyond this law of reflection.

From Six Lectures on Light Delivered In The United States In 1872-1873 by Tyndall, John