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Question
Define refraction and state the laws of refraction.
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Solution
The phenomenon of change in the direction of propagation of light when it passes obliquely from one transparent medium to another is called refraction of light.
Laws of refraction:-
- The incident ray and the refracted ray are on the opposite sides of the normal at the point of incidence, and all three lie in the same plane.
- For a given pair of media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant.
`sin i/sin r=mu`
This constant is called the refractive index of the second medium with respect to the first medium.
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| III | 50° | 36° | 50° |
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