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refraction

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noun re·frac·tion \ri-ˈfrak-shən\

Definition of refraction

  1. 1 :  deflection from a straight path undergone by a light ray or energy wave in passing obliquely from one medium (as air) into another (as glass) in which its velocity is different

  2. 2 :  the change in the apparent position of a celestial body due to bending of the light rays emanating from it as they pass through the atmosphere; also :  the correction to be applied to the apparent position of a body because of this bending

  3. 3 :  the action of distorting an image by viewing through a medium; also :  an instance of this



Did You Know?

The root of refraction is seen in the notion that the path of a ray of light or wave of energy is "broken" when it is deflected or turned. The effects of refraction can be seen in a rainbow, which is formed when light rays passing into (and reflecting out of) water droplets are bent at different angles depending on their color, so that the light separates into bands of color. The amount of refraction depends on the angle and the type of matter; refraction can occur even when passing through different kinds of air. A mirage, such as you might see in the desert or over a patch of asphalt in the summer, occurs when light passing through warm air meets the very hot air near the surface; reflecting the sky, it often resembles a lake.

Illustration of refraction

1603

First Known Use of refraction

1603


REFRACTION Defined for Kids

refraction

play
noun re·frac·tion \ri-ˈfrak-shən\

Definition of refraction for Students

  1. :  the bending of a ray when it passes at an angle from one medium into another in which its speed is different (as when light passes from air into water)




Medical Dictionary

refraction

play
noun re·frac·tion \ri-ˈfrak-shən\

Medical Definition of refraction

  1. 1:  the deflection from a straight path undergone by a light ray or a wave of energy in passing obliquely from one medium (as air) into another (as water or glass) in which its velocity is different

  2. 2a:  the refractive power of the eyeb:  the act or technique of determining ocular refraction and identifying abnormalities as a basis for the prescription of corrective lenses




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