Snell's law

American  

[snelz] / snɛlz /

noun

Optics.

1. the law that, for a ray incident on the interface of two media, the sine of the angle of incidence times the index of refraction of the first medium is equal to the sine of the angle of refraction times the index of refraction of the second medium.

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Snell's law British  

/ snɛlz /

noun

1. physics the principle that the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant when a light ray passes from one medium to another

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Etymology

Origin of Snell's law

Named after Willebrod Snell van Royen (died 1626), Dutch mathematician

Example Sentences

Snell’s law, the law of refraction, is stated in equation form as n1 sin θ1 = n2 sin θ2 .

From Textbooks • Aug. 12, 2015

Snell’s law states the relationship between angles and indices of refraction.

From Textbooks • Aug. 12, 2015

One behaves normally and is called the ordinary ray, whereas the other does not obey Snell’s law and is called the extraordinary ray.

From Textbooks • Aug. 12, 2015

The ordinary ray behaves as expected, but the extraordinary ray does not obey Snell’s law.

From Textbooks • Aug. 12, 2015

Harriot independently discovered what we now call Galileo’s law of fall, and also what we now call Snell’s law of refraction, but he never published.

From "The Invention of Science" by David Wootton